Answer:
(a) 0.500 s displacement 70.0 m - 7.2 m velocity 7.2 m/s
(b) 1.00 s displacement 70.0 m - 28.8 m velocity -13.6 m/s
(c) 1.50 s displacement 70.0 m - 57.6 m velocity -20.4 m/s
(d) 2.00 s displacement 70.0 m - 92.8 m velocity -24.0 m/s
(e) 2.50 s displacement 70.0 m -134.4 m velocity -25.2 m/s
Echolocation only works well when the object is as long as or longer than one wavelength of the sound produced.
a) Estimate the size of the smallest object a bat can detect using echolocation when the air temperature is 22 °C
The size of smallest object that a detect wing is 22°C bat can echolocation when air temperature is 31 mm.
Bat need to use because as high frequencies for echolocation compared to lower frequencies, higher. frequencies gives them more regarding size of the object in speed and frequency the prey direction of its waver are not early detailed information their path, range, pray. Also high detected by the prey.
For care the Jame of bat, dolphin frequency as explained in alio high radiation. Thus despite poor visibility under water, dolphin can high frequency and avoid to catch its wave it Predator. we there to find its path and to catch its prey and also to avoid its peredetor.
Bat sounds are emitted only during wing upbeat to minimize physiological costs. Air pressure in calls is just below blood pressure in lungs physiological maximum. FM is best for determining target distance Measure time delay between pulse and echo return FM sweep labels each part of pulse with a frequency value.
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which of the two stationary charges q1=2 c and q2=10 c will create stronger magnetic field?
Because the charges at rest are unable to produce a magnetic field, neither of the two stationary charges will do so.
There is no magnetic field created when a charge is stationary since there is no motion inside the charge. Thus, nothing except an electric field is created.
Charges that are at rest can also feel the electric force. Charges in motion can experience magnetic force. Therefore, the electric field must not be zero and the magnetic field may or may not be zero if a charged particle at rest experiences an electromagnetic force.
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You are handed a pring that i 0. 400 m long. You hang the pring from a hook
on the ceiling and attach a 0. 750-kg ma to the other end of the pring. The
tretched pring length i 0. 450 m. What i the pring contant?
The spring constant with given length that stretches upto certain length and has specified mass has a spring constant that is calculated to be 147 N/m.
Given that,
Initial length of the spring = 0.400 m
Final length of the spring = 0.450 m
Change in length, Δx = 0.450 m - 0.400 m = 0.050 m
Mass of the hung object = 0.750 kg
Weight of the hung object, w = 0.750 × 9.8 N = 7.35 N
From Hooke's law it is said that, mathematically
Spring constant = Weight of the hung object/ change in length
Putting in the above given values into the equation, we have,
Spring constant = 7.35/0.050 = 147 N/m
The required spring constant is calculated to be 147 N/m.
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At a _________ light, after checking to the rear, stop before entering the intersection or at the stop bar. If the stop cannot be made safely, proceed through the intersection with caution.
"At a yellow light, after checking to the rear, stop before entering the intersection or at the stop bar." If stopping safely is not possible, cautiously cross the junction.
Devices that are typically located at significant sites, such as busy junctions, are used to give out traffic signals in order to control the flow of traffic.
A yellow traffic light serves as a warning that the red signal will soon be shown. As a result, as soon as you notice a yellow light, you should begin to slow down in preparation for a red light. Additionally, if for some reason you are unable to stop, you should keep an eye out for any vehicles that may be approaching the intersection at the same moment.
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There is a bell on top of a tower that is 45 meters high. The bell has a mass of 20 kg. Calculate its potential energy.
Answer:
9000 Joules
Explanation:
Potential energy = mass x acceleration due to gravity x height
mass = 20kg
acceleration due to gravity = 10m/s2
height = 45 meters
20 x 10 x 45 = 9000 Joules
Gravity on the surface of the moon is only 1 6 as strong as gravity on the Earth. What is the weight of a 35 kg object on the Earth
Answer:
Weight of a 35kg object on Earth is 350N, while it is 56N on the Moon.
Explanation:
The conversion of mass (kg) to weight (N) on Earth is 1kg to 10N.
Thus, the weight of a 35kg mass on Earth is
35kg × 10 = 350N
On the Moon, conversion of mass to weight is 1kg to 1.6N.
Thus, the weight of a 35kg mass on the Moon is
35kg × 1.6 = 56N
Remember, mass remains constant regardless of location, while weight depends on the strength of the gravitational field.
The motion of a particle is described by x= 10 sin2t + 8cos2t. Determine the period, amplitude and phase angle
Answer:
Explanation:
period is 2pi / B which is 2pi/8 which is 1/4 pi
amplitude is a which is 10
A 2.0 kg book is lying on a 0.75-m-high table. You pick it up and place it on a bookshelf 2.3 m above the floor. During this process, your hand does _______ work on the book.
The weight of the book and your lifting power will be the only two forces operating, assuming that air resistance is minimal (gravity).
The book's displacement was x=(2.3-0.75)m=+1.55m.
The book weighs W= m(-g)= 2.0 kg(-10N/kg)= 20 N.
Therefore, the weight's work (energy delivered by the weight) is equal to W.x (-20N).
(+1.55m) = -31 Nm =-31 J.
This outcome, -31J, demonstrates that the weight caused the rising book to lose 31J of kinetic energy, increasing the gravitational potential energy of the book.
You lifted the book, which gave it kinetic energy from the chemical energy stored in your muscles. The weight is thereby decreasing the kinetic energy of the book while the lifting force from you increases it.
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do you think humans might be useful as index fossils in the future. Explain.
Index fossils are fossils that are used to help determine the relative age of rock layers and sedimentary strata. They are typically small, widely distributed organisms that lived for a relatively short period of time and are characteristic of a specific geological period. Index fossils are useful because they can help geologists and paleontologists to determine the relative age of rock formations and to understand the Earth's geological history.
It is unlikely that humans would be useful as index fossils in the future, as the time period during which humans have existed on Earth is relatively short compared to the age of the Earth as a whole. In addition, humans are not small, widely distributed organisms like many of the commonly used index fossils. Instead, humans are large, highly adapted organisms that have a wide range of habitats and are found on most of the continents.
However, it is possible that artifacts or other remains associated with human activity could be used as index fossils in the future. For example, the presence of certain types of tools or other materials might be used to help determine the relative age of a site or to understand the environmental conditions and human activity in a particular region at a specific point in time.
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What is the torque on the lever?
The torque of a lever is equal to the perpendicular force multiplied by the length of the lever arm, which is the distance from the fulcrum of the lever.
Where can I find torque?The formula for torque is rF=rFsin(r). Torque is, in other words, the cross product of the distance vector (the distance between the pivot point and the point at which force is applied) and the force vector, where the angle 'a' between r and F is.
What is torque, and what is its SI unit?The SI unit for torque is the Newton-metre, or kgm2sec-2. Taking into account the formula Torque = Force X Distance While distance and force are measured in meters and newtons, respectively, torque is measured in newton-meters.
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calculate the average speed of the cyclist travelling 100 meters in 40 seconds
To find the average speed of the cyclist, we need to divide the distance traveled by the time it took to travel that distance. So we would divide 100 meters by 40 seconds, which gives us 2.5 meters per second. This is the average speed of the cyclist.
Answer:
The Average Speed is 2.5metres per second
Explanation:
Using Distance,Time,Speed Triangle,
[tex]S = \frac{D}{T}[/tex]
[tex]S = \frac{100}{40}\\[/tex]
[tex]S = 2.5[/tex]
Hence , the average speed is 2.5m/s
What is the formula of law of lever?
"Effort multiplied by an arm equals burden multiplied by an arm," The various loads on the proportionally shorter load arm can be moved by the effort arm.
What does a class lever mean?A lever is a straightforward device with a solid beam and a fulcrum. The effort (input force) and load (output force) are applied to the beam's ends. The pivot of the beam is thought to be the fulcrum.
What do you name a lever?Levers are devices that increase force, to put it simply. Because they merely have the handle and the fulcrum, we refer to them as "basic machines." The "arm" of the lever is the handle or bar; it is the portion that you push against or pull towards.
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What type of resource is solar and wind?
Solar and wind are renewable resource types.
A renewable resource is an energy source that comes from nature. This is renewable and unlimited. It can be created by utilizing increasingly sophisticated technological developments so that it can become an alternative energy source.
Apart from solar and wind power, renewable energy can also be obtained from hydropower, geothermal, biomass, solar power, wind power, sea heat, waves, and tidal.
Some of the benefits of renewable resources are:
• Minimizing the effects of global warming
• Unlimited energy sources
• Save resources as well as expenses
• In several countries it can create jobs and opportunities
• Easier and cheaper maintenance
• Some technologies are easy to implement in remote areas.
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state 2 precautionary measures you would take to maintain the efficiency of an accumulator
On gas-loaded accumulators, safety devices like relief valves, burst discs, and temperature fuse plugs are all used as precautionary measures to maintain the efficiency.
What are accumulators?Accumulators are pressurized containers that can hold fluid. When a system needs a boost in power, this stored energy can be used, recharged, and then used again. The right precautions should be taken to keep pressure and temperatures under control because this stored energy can be hazardous.
On accumulators, a number of modest but crucial accessories can be placed to stop the release of this stored energy and guarantee that temperatures stay within their safe operating range.
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You are on roller blades on top of a small hill. Your potential energy is equal to 1000 joules. The last time you checked your mass was 60.0 kilograms. What is the height of the hill
The height of the hill can be calculated using the formula PE = mgh, where m is the mass, g is the acceleration due to gravity (9.8 m/s2), and h is the height of the hill. So, solving for h, we get h = PE/mg = 1000 J/ (60.0 kg*9.8 m/s2) = 10.2 m.
Therefore, the height of the hill is 10.2 m. The potential energy of an object is the energy it possesses due to its position or state. As the object moves, its potential energy can be converted into kinetic energy, or the energy it has due to its motion. In this case, the rollerblader is on top of the hill, so it has potential energy due to the height of the hill.
The formula for potential energy is PE = mgh, which means that the potential energy is equal to the mass multiplied by the acceleration due to gravity multiplied by the height. In this case, the mass is known to be 60.0 kg, and the potential energy is known to be 1000 J. By using the formula and substituting in the known values, the height of the hill can be calculated.
The height of the hill is determined to be 10.2 m, which is relatively small. This means that the hill is not too steep, and the rollerblader would not have to use a lot of energy to go down it.
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How much heat is given off when 210.0 g of water at 0°C freezes into ice?
Answer:
it gives off 71.0 kJ of heat.
Explanation:
A theme park is planning out a new free-fall ride. The drop is almost perfectly frictionless, with a distance of 190 meters. Assuming that the initial velocity was zero, what would be the speed at the bottom of the drop?
a-53 m/s
b-61 m/s
c-67 m/s
d-72 m/s
Answer:
Approximately [tex](-61)\; {\rm m\cdot s^{-2}}[/tex], assuming that [tex]g = 9.81\; {\rm m\cdot s^{-2}}[/tex].
Explanation:
Under the assumptions, the vehicle would be in a free fall. Acceleration would be constant: [tex]a = (-g) = (-9.81)\; {\rm m\cdot s^{-2}}[/tex].
Let [tex]u[/tex] denote the initial velocity of the vehicle. Let [tex]v[/tex] denote the velocity of the vehicle at the bottom of the drop. Let [tex]x[/tex] denote the displacement of the vehicle during the drop.
It is given that the initial velocity is [tex]u = 0\; {\rm m\cdot s^{-1}}[/tex]. During the drop, displacement would be [tex]x = (-190)\; {\rm m}[/tex] (negative since the vehicle is below where it started.) The value of final velocity [tex]v[/tex] needs to be found.
It is known that the vehicle is moving downwards at the end of the fall. Therefore, the value of [tex]v\![/tex] would be negative. Apply the SUVAT equation [tex]v^{2} - u^{2} = 2\, a\, x[/tex] to find [tex]v[/tex] from [tex]u[/tex], [tex]a[/tex], and [tex]x[/tex].
[tex]\begin{aligned}v^{2} &= u^{2} + 2\, a\, x\end{aligned}[/tex].
[tex]\begin{aligned}v &= -\sqrt{u^{2} + 2\, a\, x} \\ &= -\sqrt{(0\; {\rm m\cdot s^{-1}})^{2} + 2\, (-9.81\; {\rm m\cdot s^{-2}})\, (-190\; {\rm m})} \\ &\approx (-61)\; {\rm m\cdot s^{-1}}\end{aligned}[/tex].
(Note that [tex]v[/tex] is negative.)
In other words, the velocity of the vehicle would be approximately [tex](-61)\; {\rm m\cdot s^{-1}}[/tex] at the end of the drop.
2. Why might it be beneficial for a photographer to have a polarizing filter for their camera when taking pictures outdoors
A polarizing filter can be beneficial for a photographer when taking outdoor pictures because it can reduce glare and reflections from surfaces such as water and glass.
it can also enhance colors, darken blue skies, and reduce the amount of light entering the lens, allowing for more even exposure. This can be especially useful in situations where the sun is very bright and can create harsh shadows and overexposed highlights. The polarizing filter can also reduce the amount of haze in the atmosphere, which can improve the overall clarity of the image. These effects can help a photographer capture more vivid and detailed images, making them stand out from the crowd.
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Calculate the rotational inertia of 27 kg solid cylinder whose diameter is 0. 24 m about an axis of the cylinder if I= mr^2. Where I is the rotational inertia, m is mass and r is the radius
The value of moment of Inertia of the solid cylinder will be 0.19 kg/m^2
Any item that can be rotated has the property of rotational inertia. It is a scalar value that indicates how challenging it is to alter an object's rotational velocity around a certain rotational axis. The role of mass in linear mechanics is analogous to that of rotational inertia in rotational mechanics.
The formula I = 1/2 [M (R_2^2 + R_1^2)] may be used to calculate the moment of inertia of a hollow cylinder revolving along an axis passing through the centre of the cylinder. The cylinder in this instance will have a mass of M and internal and exterior radii R1 and R2, respectively.
The cylinder's moment of inertia about its axis is (MR^2)/2.
Where, M - mass of object, R = radius of the cylinder.
After putting all the values. we will get,
[tex]=\frac{27 \mathrm{~kg} \cdot(0.24 \mathrm{~m} / 2)^2}{2} \approx 0.19 \mathrm{~kg} \cdot \mathrm{m}^2[/tex]
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Among the elementary subatomic particles of physics is the muon, which decays within a few microseconds after formation. The muon has a rest mass 206.8 times that of an electron. Calculate the de Broglie wavelength associated with a muon traveling at 8.85 * 105 cm>s
By using the formulae, λ = h/mv, The De Broglie wavelength of the muon is calculated to be 4.13 × 10^10 m, as according to the given data in the question.
Is the nanosecond the shortest?The shortest measured time is 100 attoseconds. A quadrillionth of a minute is a femtosecond. One quadrillionth of a minute is a picosecond. One quadrillionth of a second is a nanosecond.
What is more compact than nano?Particles are smaller than just a nanometer. Depending on the element, an atom is between 0.1 and 0.3 nm in size. Atoms on the a surface in a SEM image.
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Light demonstrates the characteristics of _______________. particles only waves only both photons and particles both waves and particles
Both the features of waves and particles can be seen in light.only photons and particles only photons and particles, only waves.
Photons are they both waves and particles?Both a wave as well as a particle description of light are possible.The dual character of light has been highlighted in particular by two investigations.When we consider that light is composed of tiny particles, we refer to those particles as "photons."
What are waves and particles both?The following is the image for 'photons & particles combining waves and particles'.While electromagnetic radiation behaves both like a wave and a particle at the same time, it propagates according to linear wave equations and can only be released or absorbed in discrete pieces.
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Together, the car and trailer have a mass of 2000 kg. At what rate will the car and trailer accelerate?
The weight of the automobile and trailer together is 2000 kg. The vehicle will accelerate at a rate of 2.5 m/s2.
What does average acceleration formula entail?Acceleration is measured in meters per second squared (ms2), or m s 2. Formula for Average Acceleration: The final velocity minus the initial velocity, divided by the change in time, is the equation for average acceleration (a). A = v t = v f v I t.
What is the linear momentum formula?The product of an object's mass (m) and velocity (v) is its linear momentum. Higher momentum makes it more difficult to halt an object. P = mv is the equation for linear momentum.
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Why is i0 10 12 W m2 used as a reference intensity for intensity level?
Since I0 is the lowest sound intensity that a person with normal hearing can detect, it is chosen as the reference point. Given that log10 1 = 0, the decibel level of a sound with an intensity of 10–12 W/m2 is = 0 dB. In other words, the human hearing threshold is zero decibels.
The reference value I0 is 10–12 W/m2, which corresponds to the threshold of hearing intensity at 1000 Hz. The Sound Intensity Level, or SIL for short, is the intensity decibel scale. The related sign, like in our text, is LI.
Much more frequently than sound intensities in watts per square meter, sound intensity levels are expressed in decibels (dB). Both the scientific literature and the public media use decibels as their preferred measurement unit. The rationale behind this decision of units has to do with how we hear. There is a reference intensity, I0 = 1012 W/m2. The lowest or threshold intensity of sound that a person with normal hearing can perceive at a frequency of 1000 Hz is specifically known as I0. The degree of sound intensity is not the same as the intensity. is a unitless quantity that informs you of the sound level in relation to a predefined standard (1012 W/m2, in this case), as it is defined in terms of a ratio.
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A naval navigator is using sonar to look for sunken cargo. The waves he is using have a frequency of 120
kHz and a wavelength of 3 mm. How far away is the cargo if the sound wave is emitted at exactly 9:24 a.m.
and returns to hit the ship's sensor 3 seconds later?
Answer should be in meters
With the use of wave speed and echo formula, the distance is 540 m
What is Echo ?Echo can simply be defined as a reflection of sound wave. Where as, Sound wave is longitudinal wave.
Given that a naval navigator is using sonar to look for sunken cargo. The waves he is using have a frequency of 120 kHz and a wavelength of 3 mm.
The wave speed V = Fλ
Where
V = ?F = 120 KHz = 120,000λ = 3 mm = 0.003 mV = 120000 × 0.003
V = 360 m/s
How far away is the cargo if the sound wave is emitted at exactly 9:24 a.m. and returns to hit the ship's sensor 3 seconds later?
Speed V = 2S/t
where
S = distance ?t = time taken = 3 s360 = (2 × S)/3
360 × 3 = 2S
S = 1080/2
S = 540 m
Therefore, the cargo is 540 m away
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600 Joules of work is used to lift a box from the ground to a height of six meters. How much work would have been done if a lever would have been used with an effort arm of 12 meters and a load arm of 6 meters? (10 points)
a. 72 J
b. 100 J
c. 50 J
d. 600 J
Answer:
d. 600 J
Explanation:
You want to know the work done to lift a box using a lever with a mechanical advantage of 2, if the work required without the lever is 600 J.
LeverA lever trades force for distance. That is raising the box a distance of 6 m requires moving the lever arm a distance of 12 m, but only half the force is required. The product of force and distance is the same.
The total required work is unchanged: 600 J.
__
Additional comment
Actually, more work is required to lift the box using the lever. There is work applied to the box, and there is more work applied to moving the lever. (We have to assume a massless lever with no friction in these problems.)
1. What is the
momentum of a 1.5 × 103-kilogram car
as it travels at 30. meters per second due east for 60.
seconds?
A) 4.5 x 104 kg m/s, east
B) 4.5 x 104 kg.m/s, west
C) 4.5 x 106 kg•m, east
D) 4.5 x 106 kg•m, west
A 1.5 x 103 kg car's momentum is equal to 4.5 x 104 kg m/s east if it moves at a speed of 30 m/s for 60 seconds while traveling straight east.
What is momentum ?Momentum is a property of an object or system that describes its tendency to move or stay in motion. It is equal to the product of the mass of the object and its velocity. Momentum is conserved, meaning that the total momentum of an isolated system remains constant, regardless of any changes or interactions within the system. Momentum is an important concept in classical mechanics, and is directly related to forces, energy, and angular momentum. Momentum is an essential factor for describing the behavior of objects in motion.
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given the masses of p1, p2, p3, and p4 are respectively 1kg, 2kg, 3kg, and 4kg, determine the value of the greatest horizontal range of the four projectiles, assuming they land at the same height that they fire at.
As Projectile range is independent of mass, so They all will have same range.
When an object is close to Earth's surface, its gravitational attraction is calculated using the formula F = mg, where m is the object's mass and g is a constant whose value varies depending on the location. On the surface of the earth, it averages 9.81 meters per second. And when one moves away from the surface in either an inner or an outward direction, this value drops.
Although the strength of the earth's gravitational pull changes depending on the mass of the object, the acceleration caused by it is constant (of course close to the surface). Consequently, when two items of different masses are dropped from the same height, they hit the ground simultaneously (neglect air resistance).
Any motion of a projectile simply consists of vertical and horizontal motion. Regardless of the direction the projectile is going in, gravity controls vertical motion since it only acts in that direction. Additionally, the acceleration caused by gravity is not reliant on the mass of the item. Therefore, the mass has no bearing on the vertical motion.
A projectile moves horizontally in a very straightforward manner. A projectile is not affected by horizontal forces. As a result, its horizontal velocity does not change. Additionally, the range is influenced by horizontal velocity and flying time. Flight time is influenced by vertical motion.
We now know that mass has no bearing on flying duration or range. And if you run into a projectile motion problem, simply divide the problem into horizontal and vertical motions. And handle it the same way you would a single-direction motion. greatly simplifies matters.
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You may think of a sheet of aluminum foil as a 2D object, but it is really a 3D object because it has a non-zero thickness. Consider a sheet of aluminum foil that is 17.4 inches by 14.8 inches and has a mass of 10.8 grams. Of the density of aluminum is 2.7 g/cm3, what is the thickness of the foil in mm
Answer:
Below
Explanation:
17.4 inches = 441.96 mm 14.8 inches = 375.92 mm
volume = 441.96 X 375.92 X T
= 166141.6 T mm^3 <===where T = thickness in mm
Volume X density = mass
166141.6 T mm^3 * 2.7 gm/cm^3 * cm^3 / 1000mm^3 = 10.8 gm
solve for T = .024 mm
Of the following objects, on which one would time on its surface run most slowly?
a. An object with the same mass as the Sun but twice as large in radius
b. The Sun
c. An object with the same mass as the Sun but only half as large in radius
The time on the surface of an object would run most slowly on an object with the same mass as the Sun but twice as large in radius.
What is mass?
Mass is a measure of the amount of matter in an object and is typically expressed in kilograms (kg). It is an intrinsic property of matter and is different from weight, which is a measure of the force of gravity acting on an object. Mass is an important factor in determining the physical properties of an object, such as density, momentum, and inertia. Mass is also used to calculate the gravitational force between two objects, as well as the energy required to move it.
This is because the surface gravity of an object is inversely proportional to the square of its radius. Therefore, the object with the same mass as the Sun but twice as large in radius would have a much lower surface gravity, and time would run more slowly on its surface.
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20 points!
A student wants to measure the diameter of a ping pong ball, a golf ball, and a baseball.
Which SI unit should the student use?
centimeters
moles
kilometers
milligrams
Answer:
Centimeters.
Explanation:
There are only 2 viable answers here. This is due to the fact that moles are used not to measure diameters but instead the number of atoms.
Similarly, milligrams are not used to measure diameters but instead small volumes.
This leaves us with kilometers and centimeters, and since all 3 objects are more easily representable in centimeters than kilometers, the answer must be centimeters. One example would be the diameter of a ping pong ball, which is approximately 4cm, or in other words, 0.00004km, with 4cm being much more easy to represent as it overall involves less digits.