The angle turned in 5.26 s is 6470 degrees. An initial angular speed of 12.5 rad/s and a constant angular acceleration of 3.41 rad/s2 are the characteristics of a pulley.
Does acceleration affect angular velocity?The angular acceleration provides the rate of change of angular velocity, just like in the case of linear velocity and acceleration: The rate at which the angular velocity varies is determined by the angular acceleration's magnitude, and the change's direction is determined by the direction.
What is the formula for angular acceleration?The rate at which angular velocity changes is referred to as angular acceleration. In an equation, angular acceleration is written as follows: = t, where t is the change in time and is the change in angular velocity.
To know more about angle turned visit:
brainly.com/question/29160335
#SPJ4
Which of the following properties of a 2.3 MHz ultrasound wave remains unchanged as it passes into human tissues
When it comes to frequency, a 2.3 MHz ultrasonic wave's characteristic does not alter while it travels through human tissues.
The frequency of a wave is the number of oscillations it performs in a second. It's calibrated in hertz (Hz). The number of waves that pass a specific place in a predetermined period of time is known as wave frequency. The hertz (Hz) is the SI unit for wave frequency, and 1 hertz is equivalent to 1 wave crossing a fixed point in 1 second. A wave with a higher frequency has more energy than a wave with a lower frequency of the same amplitude.
As a result, a wave's frequency is unaffected by the medium through which it travels.
To know more about the Frequency of a wave, refer to this link:
https://brainly.com/question/14316711
#SPJ4
The Cessna Cardinal, a single-engine light plane, has a wing with an area of 16. 2 m^2, and an aspect ratio of 7. 31. Assume the span efficiency factor is 0. 62. A. If the airplane is flying at standard sea-level conditions with velocity of 251 km/h, what is the induced drag when the total weight is 9800N b. Calculate the induced drag when the
The Cessna Cardinal, a single-engine light plane, has a wing area of 16.2 m² and an aspect ratio of 7.31 with span efficiency factor of 0.62 then the induced drag when the total weight is 9800 N is 18.8 N.
Given that,
Wing area (A) = 16.2m²
Aspect ratio (r) = 7.31
Efficiency factor (e) = 0.62
Weight of plane (W) = 9800 N
Velocity of airplane (v) = 251 km/h = 251× 5/18 = 69.72 m/s
We know,
Dynamic pressure (p) = 1/2ρv²
where ρ is density of plane = 1.225
p = 1/2 × 1.225 × 69.72 × 69.72 = 2977.29 pa
Lift coefficient Cl = W/p × A = W/(1/2ρv²) A
where, A is the area of wing
Cl = 9800/2977.29 × 16.2 = 0.203
Induced drag coefficient (Cd) = Cl²/πer² = (0.203 × 0.203)/(π × 0.62 × 7.31 × 7.31) = 0.041/(104.08) = 0.39×10⁻³
Induced drag (d) = p × A × Cd = 2977.29 × 16.2 × 0.39 × 10⁻³ = 18.8 N.
To know more about drag:
https://brainly.com/question/30024162
#SPJ4
What would be the strength of Earth's gravitational field at a point where an 80. 0 kg astronaut would experience a 80% reduction in weight
Answer:
W = m g = 80 kg * 9.80 m/s^2 = 784 N using g = 9.80 m/s^2
W' = (W - .8 W) 80 = .2 W = 157 N
W' = 80 kg * g' = 157 N where g' is the reduced field
g' = 1.96 m / s^2
Find the y-component of this vector: 22.3 m 77.1° Remember, angles are measured from the +x axis.
Answer:
-21.7m
Explanation:
To find the y-component of the vector, we need to find the vertical displacement from the point at the bottom of the vector to the x-axis (or its y-coordinate value).
To calculate this we can create a triangle with the vector as the hypotenuse, the y-axis as the second side and draw an imaginary line from the end of the vector directly horizontally across to the y-axis.
We can use the given angle to find the angle between the y-axis and the angle. Since the angle of a quadrant is 90 degrees, the angle within our triangle must be [tex]90-77.1=12.9[/tex] degrees.
From here, to find the length of the side on the y-axis we can use the trigonometric cos function.
[tex]cos \theta =\frac{adjacent side}{hypotenuse}[/tex]
Therefore [tex]cos 12.9=\frac{y-component}{22.3}[/tex] and [tex]ycomponent = 22.3cos12.9[/tex]
This gives us a value of 21.7 (3.s.f) for our y-component.
Finally, the y-component is also a vector so it also needs a direction. Therefore like its coordinate, its value will be -21.7m.
What is the SI unit of momentum?
Answer:
kgm/s(-1)
Explanation:
the units of momentum will be the product of the units of mass and velocity. Mass is measured in kg and velocity in ms-1, therefore, the SI unit of momentum will be kgm/s(-1).
The set of spectral lines that we see in a star's spectrum depends on the star's (a) atomic structure. (b) chemical composition. (c) rotation rate.
The set of spectral lines that we see in a star's spectrum depends on the star's (b) chemical composition, (d) temperature.
The spectral lines of a star are determined by its chemical composition and temperature. These properties determine the number and type of atoms present in the star's atmosphere. Each type of atom has its own unique set of spectral lines, and the temperature of the star determines the energy level of the atoms, which affects the wavelengths of the spectral lines emitted. The rotation rate and atomic structure of a star do not affect the set of spectral lines we see in its spectrum.
learn more about spectral lines here
https://brainly.com/question/27494244
#SPJ4
Estimate the length of a human lifetime, in seconds. Consider a life expectancy of 80 years. Express your answer in seconds.
A human lifetime of 80 years is equal to 29,200,000 seconds.
What is human lifetime?The average human lifetime is typically 79 years, although this can vary greatly depending on various factors such as lifestyle, genetics, and environment. Generally, most people can expect to live anywhere from their late 60s to their mid-80s. However, some people live much longer, and some much shorter. Even within the same family, the range of lifespans can be quite varied.
This can be calculated by multiplying the number of seconds in a day (86,400) by the number of days in a year (365) by the number of years in a human lifetime (80).
86,400 x 365 x 80 = 29,200,000 seconds
To learn about more human lifetime.
https://brainly.com/question/11105393
#SPJ4
13. Shadrach, a form one student performed an experiment to investigate surface tension. he poured some water on a trough and allowed it to settle he then took a razor blade and gently placed it on the surface of the water in an attempt to make it float but failed give two possible reasons why the experiment failed
Answer:
this because the surface tension was lowered by using an impurity or rising the temp of the water
Answer the questions based on the information given. The Amur plate, a small plate, has moved away from the Eurasian plate. It has moved125,000 meters in 25 million years. It is moving eastward. What is the rate of motion of the Amur plate
The solutions are: The movement is 5 mm per year. The plate is 5,000 meters to the east. The Amur and Eurasian plates would collide, creating an ocean floor.
The rate of motion is in mm per year so you need to convert the distance it has moved to millimeters.
1 meter = 1,000 meters
125,000 will therefore be:
= 125,000 * 1,000
= 125,000,000 millimetersRate of motion = 125,000,000 / 25,000,000 years
= 5 mm/year
The plate is moving east and in 1 million years it would be:
= 1,000,000 * 5 mm/year
= 5,000,000 mm
n meters this is:
= 5,000,000 / 1,000
5,000 meters east
ecause the Amur and the Eurasian plates are moving apart, the ocean would have to fill up the space left which would lead to the development of a new oceanfloor.
Learn more about motion here-
https://brainly.com/question/22810476
#SPJ4
Answer: 5 mm/year, 5000 meters east, new ocean floor
Explanation:
Suppose that the railcar passes by a horn that is emitting a sound with frequency f. Which of the following describes the frequency f PS-10-1-prime.gif that the person on the railcar hears?
A. f PS-10-1-prime.gif > f before passing the horn, f PS-10-1-prime.gif < f after passing it
B. f PS-10-1-prime.gif < f before passing the horn, f PS-10-1-prime.gif > f after passing it
C. f PS-10-1-prime.gif = f before passing the horn, f PS-10-1-prime.gif = f after passing it
D. f PS-10-1-prime.gif > f before passing the horn, f PS-10-1-prime.gif > f after passing it
F PS-10-1-prime.gif > f before passing the horn, f PS-10-1-prime.gif < f after passing it describes the frequency f PS-10-1-prime.
Hence, Option A is correct.
The Doppler effect causes the frequency heard by the railcar passenger prior to passing the horn to be higher than the real frequency of the sound released, whilst the frequency heard after passing the horn is lower than the actual frequency. This is why the answer to this question is A. A railcar is a self-propelled passenger-carrying railroad vehicle. A train with a single coach and a driver's cab at one or both ends is typically referred to as a "railcar." Such vehicles are referred to as "railmotors" by several railway companies, including the Great Western.To know more about railcars here
https://brainly.com/question/14652521
#SPJ4
A golf ball rolls up a hill toward a miniature-golf hole. Assign the direction toward the hole as being positive. a. If the ball starts with a speed of 2.0 m/s and slows at a constant rate of 0.50 m/s2, what is its velocity after 2.0 s
The velocity of the ball is 1 m/s which starts with a speed of 2.0 m/s and slows at a constant rate of 0.5 m/s².
According to the data given:
Speed of the ball: 2.0 m/s
Acceleration: 0.50 m/s²
Time is 2.0 s
The ball starts rolling up the hill with a speed of 2m/s (u=2 m/s²) and it decelerates at a constant rate of 0.5 m/s² (a = -0.5 m/s², minus because it decelerates).
The equation for calculating velocity is:
v = u + a x t, t represents time here
So, ball's velocity after 2 seconds is:
v = 2m/s + (-0.5m/s² x 2s)
v = 2m/s + (-1m/s)
v = 1m/s
Learn more about acceleration:
brainly.com/question/28743430
#SPJ4
Ball A od mass 5.0 kilograms moving at 20. meters per second colides with ball B of imknnown mass moving at 10 meters per scond in the same direction. After the collision, ball A movies at 10. meters per second and ball B at 15 meters per second, both still in the same direction. What is the mass of ball B
Answer:
10 kg
Explanation:
Use law of conservation of momentum
momentum of system before collision = momentum of system after collision
5 kg * 20 m/s + x kg * 10 m/s = 5 kg * 10 m/s + x kg * 15 m/s
100 + 10x = 50 + 15 x
50 = 5x
x = 10 kg
The resistance of a filament that carries 2 A when a 10-V potential difference across it is. A) 2 ohms. B) 5 ohms. C) 10 ohms. D) 20 ohms.
The resistance of the filament which carries the current of 2 A and has a potential difference of 10 V is b) 5 ohms
The current passing through the filament = 2A
The potential difference in the filament = 10 V
The resistance of the filament can be found using the formula,
R = V/I
where R is the resistance of the filament
V is the potential difference between the filament
I is the current passing through the filament
Let us substitute the known values in the above equation, we get
R = 10 / 2
= 5 ohms
Therefore, the resistance of the filament is 5 ohms
Learn more about the resistance in
https://brainly.com/question/29427458
#SPJ4
If an amount of heat Q is needed to increase the temperature of a solid metal sphere of
diameter D from 4°C to 7°C, the amount of heat needed to increase the temperature of a solid
sphere of diameter 2D of the same metal from 4°C to 7°C is
A. 8Q
B. 40
C. 20
D. Q
As a result, X heat required = 27Q is the amount of heat needed to raise the temperature.
Calculationfirst case
Q = Specific Heat * Density of Sphere* (4/3*pi*D^3) * (7-4) -1
Second case
X = Specific Heat * Density of Sphere* (4/3*pi*(3D)^3) * (7-4) -2
Dividing 1 and 2 we get
Q/X = 1/27
27
How does the heat equation's Q work?where Q is the amount of heat that is transported to or from the item, m is the object's mass, C is the material's specific heat capacity, and T is the resultant temperature change of the object.
to know more about the heat here:
brainly.com/question/1429452
#SPJ4
An electric cord can be stretched to its elastic limit by a load of 3N. If a 350cm length of the cord is extended by a force of 0.5N, what will be the length of the cord when the stretching force is 2.5N?
Answer:
359cm
Explanation:
The change in length of the cord due to a stretching force of 0.5N is given by Hooke's law:
ΔL = k * ΔF
Where ΔL is the change in length, k is the spring constant and ΔF is the change in force.
Since the spring constant for the cord is 3N/cm, the change in length due to a stretching force of 0.5N is:
ΔL = (3N/cm) * (0.5N) = 1.5 cm
Since the cord is already 350cm long, the total length of the cord when the stretching force is 0.5N is 350cm + 1.5cm = 351.5cm.
To find the length of the cord when the stretching force is 2.5N, we can use the same formula:
ΔL = (3N/cm) * (2.5N) = 7.5 cm
The total length of the cord when the stretching force is 2.5N is therefore 351.5cm + 7.5cm = 359cm.
Drag each label to the correct location.
Identify the boundary type that is being described.
Transform boundaries, continental convergent boundaries, and oceanic convergent boundaries are the boundaries that are recorded.
How do transform boundaries work?A transform boundary is an area of a fault where two surfaces slide horizontally past one another.
What exactly is a convergent ocean boundary?An oceanic convergent boundary is the collision of two oceanic lithosphere-based plates. Even if this boundary contained the same kind of lithosphere, one of the plates would subduct beneath the other.
Transform boundaries are where crust is neither created nor destroyed at this boundary.In the region where the plates come into contact, movement along this boundary causes crumpling, lifting, and folding of the earth's crust—the continental convergent boundary.At this boundary, also known as the oceanic convergent boundary, the subduction zone frequently forms an arc of volcanic islands.To learn more about Transform boundaries here:
https://brainly.com/question/28641825
#SPJ1
1. When conducting a test on what kind of music increases the growth of plants, all of the following would fail to meet to fair test standard EXCEPT (1 point)
using different kinds of plants.
giving some plants more water than others.
exposing the plants to different types of music.
using nutrient-rich soil for one and lesser soil for others.
2. Engineering uses scientific thinking to solve real-world problems. (1 point)
True
False
3. What does it mean to test a hypothesis? (1 point)
Pass a quiz on other scientists’ results
Analyze only the results from scientific sources
Not make assumptions about how an experiment will turn out
See if the results of an experiment are what the scientist predicted
Using a specific kind of raga played over a gramophone and loudspeakers, Singh replicated the experiment with field crops. Crop sizes grew to 25–60% over the average for the region. According to Singh, the violin's music has the biggest impact on plant development.
What interactions do nutrients have with one another in the soil?Nutrient interactions in the soil, which alter the availability of nutrients to plants, illustrate the range of interactions that may take place. High concentrations of one nutrient in the soil can conflict with the availability and absorption of other nutrients.
Which soil has the greatest concentration of nutrients?Loamy soils, which combine sand, clay, and silt particles, are thought to be the most fertile form of soil.
To know more about plant development visit :-
https://brainly.com/question/29123942
#SPJ4
a car with a mass of 900kg how many is the car weight on earth?
Answer:
9000N
Explanation:
gravitational field strength of earth is approximately 10N/kg .
900kg×10N/kg
=9000N
What is the magnitude of the passenger's acceleration as she passes through the lowest point in her circular motion
The magnitude of the passenger's acceleration as she passes through the lowest point in her circular motion is the centripetal acceleration.
This is given by the equation a = v^2 / r, where v is the velocity of the passenger and r is the radius of the circle. Therefore, the magnitude of the passenger's acceleration is equal to the square of her velocity divided by the radius of the circle.
For example, if the passenger is travelling at 10 m/s in a circle with a radius of 5 m, then her centripetal acceleration would be 10^2 / 5 = 20 m/s^2.
Learn more about acceleration:
https://brainly.com/question/460763
#SPJ4
You rub a piece of wool upon your skin and your skin becomes negatively charged because it gained _____.
When you touch a piece of wool against your skin, your skin acquires a negative charge because of the conservation of charge, which caused it to gain a positive charge.
Charge is a material's property that can be transferred into another person's body. The transfer of the charge results in the generation of electricity. The following are some examples of charge's various properties: 1 Electric charge addition 2 Electric charge conservation 3 Electric charge quantization. Equations in chemistry are denoted by the capital letter Q to denote charge, with the elementary charge of an electron (e) serving as a standard unit. The coulomb is the SI-derived unit of charge (C). In electrical engineering, the ampere-hour (Ah) unit of charge is frequently used.Dipole Definition in Chemistry and Physics. by this primary information we can consider that when you rub a piece of wool upon your skin and your skin becomes negatively charged because it gained a positive charge as the result of conservation of charge.
Learn more about Charge:
brainly.com/question/3412043
#SPJ4
A crate is carried in a pickup truck traveling horizontally at 15.0 m/s. The truck applies the brakes for a distance of 28.7 m while stopping with uniform acceleration. What is the coefficient of static friction between the crate and the truck bed if the crate does not slide
The truck bed and the crate's static coefficient of friction, assuming the crate doesn't slide, is 0.400.
In the event that the container does not slide, what is the coefficient of static friction between the crate and the truck bed?Between the truck bed and the crate, there is 0.64 coefficient of static friction. When the bed is in the position depicted, the truck must move quickly to the right in order to make the crate slide.
The coefficient of static friction can be calculated in what way?The resistive friction force (Fr) divided by the normal or perpendicular pushing force (N) yields the coefficient of friction, which is a numerical value. The formula fr = Fr/N is used to represent it.
To know more about static friction visit:-
https://brainly.com/question/13000653
#SPJ4
How much of the world's energy is hydroelectric?
According to the United Nations Environment Programme, hydropower accounted for 16.6% of global electricity generation in 2018.
This is equivalent to a total installed capacity of 706 GW, making it the second largest energy source after thermal sources.
Hydropower is a renewable energy source and is often seen as a more sustainable alternative to thermal sources, as it does not release any greenhouse gases into the atmosphere. Additionally, hydropower is a reliable source of energy, and can be used to meet peak energy demand.
Learn more about hydroelectric energy:
https://brainly.com/question/3077353
#SPJ4
The connected bar BC is used to increase the lever arm of the crescent wrench as shown. If a clockwise moment of MA = 120 N·m is needed to tighten the nut at A and the extension d = 300 mm, determine the required force F in order to develop this moment. 15° F 30 300 mm А Probs. 427/28/29
The value of d is 401.550.
Momentum can be viewed as a body's "power" while it is moving, or the amount of force it can exert on another body. For instance, a baseball (small mass) thrown quickly can have the same momentum as a bowling ball (big mass) going extremely slowly (low velocity) (high velocity).
"The motion of an item equal to the product of its mass and its velocity" is referred to as momentum. When we say anything has momentum, we are referring to its precise mass and direction of motion.
C+ΣMA = ( 200 cos 45) (d cos 30+0-3) -
(200 sin 45°) (d sin 30°)= -120
(200COS 45°) (0.3) + (200 cos 45°) (d cos30) +
(200sin 45') (d sin 30") = 120
d = 120- (200 cos 45) (0.3) / 200 (cos 45 Cos 30+ sin 45 sin 30)
d = 0.40155m
d = 401.55mm
d = 401.550
To learn more about momentum from given link
https://brainly.com/question/18798405
#SPJ4
Complete Question -
A block is resting on an slope. (Figure 3) Which of the following forces act on the block? Check all that apply. O weight O static friction O normal force O kinetic friction O force of push
The correct option is A, B, and C. A block resting on a slope is Weight, static friction, and Normal force.
Static friction is a force that continues an item at relaxation. Static friction definition can be written as: The friction skilled while individuals try to move a desk-bound object on a surface, without surely triggering any relative movement between the frame and the surface on which it's miles.
Static friction is a form of friction force that acts on a body when there's no relative motion between the object and the surface. So, it can act even if the frame is in motion however there should be no relative motion.
A pressure acting on an item is said to be a static force if it no longer exchanges the scale, function, or route of that precise object. The pressure implemented to a structure acts as a load to that precise structure, that is why static force is likewise called a static load.
To learn more about Static friction visit here:
brainly.com/question/13000653
#SPJ4
Complete Question:
A block is resting on a slope. (Figure 3) Which of the following forces act on the block?
Check all that apply.
A). Weight
B). Static friction
C). Normal force
D). Kinetic friction
E). Force of push
A 1,000-kilogram car traveling with a velocity of +20 meters per second decelerates uniformly for 4 seconds until it comes to rest. Calculate the net force on the
car in Newtons
The required net force on the car with certain mass and travelling with deceleration is said to be 5000 N.
Given that,
Mass of the car m = 1000 kg
Velocity of the car v = 20 m/s
Time t = 4 sec
Net force on the car = ?
According to Newton's second law of motion, it is said mathematically that, F = m a ---(1)
Acceleration a can be written as the rate of velocity.
a = (v-u)/t = (0 - 20)/4 = - 5 m/s² ---(2)
Substituting (2) in (1) we have,
F = m a = 1000 × - 5 = -5000 kg m/s² or -5000 N
Thus, the required net force on the car is 5000 N.
To know more about force:
https://brainly.com/question/1005491
#SPJ4
The impulse that the pelton wheel applies to the water is ___ the change in momentum of the water after hitting the flat paddle wheel?
The impulse that the pelton wheel applies to the water is equal to the change in momentum of the water after hitting the flat paddle wheel.
What is the pelton wheel about?Impulse is a measure of the force applied to an object over a period of time, and it is equal to the change in momentum of the object.
In the case of the pelton wheel, the force is applied to the water by the flat paddle wheel, and the change in momentum of the water is the result of that force.
Therefore, The impulse of the pelton wheel is therefore equal to the change in momentum of the water after it hits the paddle wheel.
Learn more about pelton wheel from
https://brainly.com/question/20038787
#SPJ1
If the absolute temperature of an object is tripled, the thermal power radiated per unit surface area of this object will (assuming that its emissivity is not affected by the temperature change)?
Answer: increase by a factor of 81
A temperature increase of an order of 81 will cause an object's thermal output radiated per unit surface area to double, assuming that its emissivity is unaltered by the temperature change.
By dividing the Planck radiation density by a wavelength interval, you can compute it numerically.The rate of heat transfer through radiation emitted is controlled by the Stefan-Boltzmann law of radiation: Qt=σeAT4 The equation Q t = e A T 4 includes the Stefan-Boltzmann constant, A, the object's surface area, and T, the object's absolute temperature in kelvin.All bodies emit energy W depending on temperature T according to the Stefan-Boltzmann formula W = T4, where emissivity is equal to 1 for black bodies and less than 1 for grey ones, being the Stefan constant.To know more about Temperature here
https://brainly.com/question/24746268
#SPJ4
Mercury thermometer is not suitable to measure the temperature of very cold place. Why?
The use of a mercury thermometer is not suitable for the purpose of determining the temperature of extremely cold ice because at such low temperatures, mercury transforms into a translucent state, making it impossible to read.
Another reasons why mercury thermometer is not suitable to measure the temperature of the very cold place are:
Since mercury freezes at a temperature of -38.83 degrees Celsius, a mercury thermometer will not work in extremely cold temperatures. We are unable to use a thermometer that contains mercury at low temperatures because the glass could shatter at those temperatures.The body whose temperature we are measuring with the thermometer does not radiate heat in the opposite direction.When exposed to low temperatures, mercury takes on a transparent appearance, making it more challenging to obtain accurate readings.To learn more about mercury thermometer, click here:
https://brainly.com/question/28442913
#SPJ4
In designing rotating space stations to provide for artificial-gravity environments, one of the constraints that must be considered is motion sickness. Studies have shown that the negative effects of motion sickness begin to appear when the rotational motion is faster than approximately 1.65 revolutions per minute. On the other hand, the magnitude of the centripetal acceleration at the astronauts' feet should equal the magnitude of the acceleration due to gravity on earth. Thus, to eliminate the difficulties with motion sickness, designers must choose the distance between the astronaut's feet and the axis about which the space station rotates to be greater than a certain minimum value. What is this minimum value
This minimum value is 223.9 m.
The attribute of motion of an item travelling a circular path is characterised as centripetal acceleration. Centripetal acceleration is defined as any item travelling in a circle with an acceleration vector pointing towards the centre of that circle.
The acceleration felt when moving in a uniform circular motion is known as centripetal acceleration. It always points toward the rotational centre. It is parallel to the linear velocity. The centripetal force is measured in an inertial frame of reference, whereas the centrifugal force is measured in a non-inertial frame of reference. Centripetal force is directed towards the axis of rotation or the centre of curvature, whereas centrifugal force is directed away from the circle's centre.
To learn more about centripetal acceleration, here
https://brainly.com/question/14465119
#SPJ4
When a rubber rod is rubbed with wool, the rod becomes negatively charged. What can you conclude about the magnitude of the wool's charge after the rubbing process
The wool must start out negatively charged before becoming positively charged after donating its electrons to the rubber rod.
What happens when wool is rubbed on a rubber rod?A rubber rod becomes negatively charged when wool is brushed against it, and the magnitude of the charge on the wool is equal to the charge on the rod. By applying the same amount of negative charge to the rod, the wool becomes positively charged.
Why does a polythene rod become negatively charged when it is brushed against wool?Electrons generate energy while rubbing a polythene rod with a duster because of the friction. When they have enough energy, electrons can escape from an atom and "rub off" onto a polythene rod.
To know more about electrons visit:
brainly.com/question/12240595
#SPJ4