Hiro walks up a flight of stairs in his apartment building. Later in the day, he runs up the same flight of stairs.
Which statement about work and power describes Hiro’s actions?
He did more work running than walking.
He did more work walking than running.
He had more power running than walking.
He had more power walking than running.
Answer:
C) he had more power running than walking
Explanation:
saw it on a quizlet. not 100% sure tho
Hiro walks up a flight of stairs in his apartment building. Later in the day, he runs up the same flight of stairs so He had more power running than walking.
What is power?In physics, power is the amount of energy transferred or converted per unit of time. In the International System of Units, the unit of power is the watt, equal to one joule per second. In older works, power is sometimes called activity. Power is a scalar quantity.
Power is related to other quantities; for example, the power involved in moving a ground vehicle is the product of the traction force on the wheels and the velocity of the vehicle.
The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft
Since we know that Hiro will run on stairs to minimize the time of reaching his home so if time decreases then he has to increase his power as power is the ratio of work and time.
Hence Hiro walks up a flight of stairs in his apartment building. Later in the day, he runs up the same flight of stairs so He had more power running than walking.
To know more about power follow
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7. A car is moving at 50.0 mph when the driver applies brakes. Determine the distance it
covers before coming to a halt. Coefficient of static friction between the tires and surface of
the road is 0.514. Mass of the car is 1000 kg.
Answer:
The distance to come to a halt is approximately 49.53 meters
Explanation:
Thee given parameters are;
The speed of the car, v = 50 mph = 22.35 m/s
The mass of the car, m = 1000 kg
The coefficient of friction, = 0.514
The force of friction of the brake = Mass × Gravity × Friction = 1000 × 9.81 × 0.514 = 5042.34 N
The initial kinetic energy of the car = 1/2×m×v² = 1/2 × 1000 × 22.35² = 249761.25 J
The work done by the brake = Force of the brake × Distance, d, to come to halt
By conservation of energy, we have;
The work done by the brake = The initial kinetic energy of the car
∴ The initial kinetic energy of the car = Force of the brake × Distance, d, to come to halt
The initial kinetic energy of the car = 249761.25 J = 5042.34 N × Distance, d, to come to halt
∴The distance to come to a halt = 249761.25 J /(5042.34 N) ≈ 49.53 meters
The distance to come to a halt ≈ 49.53 meters.
The car will cover 49.65 m distance before stopping due to application of brake.
Given data:
The mass of car is, M = 1000 kg.
The initial speed of car is, u = 50.0 mph = (50)(0.447 m/s) = 22.35 m/s.
The coefficient of static friction is, [tex]\mu = 0.514[/tex].
The given problem can be solved using the third kinematic equation of motion. Which is,
[tex]v^{2}=u^{2}+2as[/tex] ....................................................(1)
Here, v is the final speed, v = 0 (Because car is finally stopping)
s is the distance covered before stopping and a is the magnitude of acceleration.
Now, since frictional force opposes the motion. Then,
[tex]F = f\\\\ma = \mu \times m \times g\\\\a = 0.514 \times 9.8\\\\a =5.03 \;\rm m/s^{2}[/tex]
Substituting the values in equation (1) as,
[tex]0^{2}=23.35^{2}+2(-5.03)s\\\\s = \dfrac{2500}{2 \times 5.03}\\\\ s=49.65 \;\rm m[/tex]
Thus, the car will cover 49.65 m distance before stopping due to application of brake.
Learn more about the Kinematic equations of motion here:
https://brainly.com/question/14355103
A projectile is launched with an initial velocity of 1.414 m/s at 45° above the horizontal. What is the vertical component of the projectile's velocity when it strikes a wall 0.50 m away?
Answer:
As the projectile starts it’s motion from a vertical height at y=10m, it’s vertical motion may be described as under-
y= 10+ut-0.5gt^2
Where “u” is initial vertical velocity
= 45 sin60,
“g” is acceleration due to the gravity (10m/sec^2)
and “t” is time.
When the projectile touches the ground the vertical height “y”=0
Therefore the time “t” taken for the flight of the projectile till it touches the ground may be calculated from the above equation when y=0 as under -
0= 10+45sin60 x t- 0.5x10 t^2
0= 10+45x (√3/2)x t-5 t^2
t^2-9x (√3/2)x t-2 =0
t= [4.5√3 + √(243/4+4)]/2
t=[7.794+ 8.047]/2
t= 7.92 sec.
The horizontal distance travelled during this time=
vt
Where “v” is horizontal velocity = 45 cos60.
Therefore,
vt =45cos60 x 7.92
= 45x0.5x7.92
= 178.2 m
A force of 75 N at an angle of 15° to the direction of motion moves a chair 3 m. Which change would result in more work being done on the chair?
Answer:
Decreasing the angle to 10
Explanation:
Edge 2020
Where would the net force acting on a charge placed in a system of like charges be zero?
Answer:
If an object is electrically neutral it has no net charge becuase it has the same number of protons as it does electrons, which are opposite charges that offset each other. No, that just means that the sum of all its positive and negative amounts of charge equals zero.
During a car trip across the state of Ohio you travel 275 miles in 6 hours.
What was your average speed for the entire trip(in mph)?
Answer:
45.83MPH
Explanation:
Let's use equivalent ratio.
275 miles = 6 hours
6 / 6
45.83 miles = 1 hour
Which of the following is a solution?
OA.
ocean water
OB. oil in water
OC. sand in water
OD. all of these
OA. Ocean water
Answer:
OA. ocean water is a solution
Explanation:
Cody’s car accelerates from 0M/S 245 in/at Northwoods and 15 seconds what is the acceleration of the car
Answer:
3m/s^2
Explanation:
Acceleration is change in velocity / time = 45/15 = 3m/s^2
Two students described a part of Earth's innermost layer.
Daniel: Densest part
Joshua: Has highest temperature and pressure
Which part of the innermost layer did Daniel and Joshua describe?
They both described the outer part.
They both described the inner part.
Daniel described the outer part and Joshua described the inner part.
Daniel described the inner part and Joshua described the outer part.
Answer:
It is B
Explanation:
Because the high temp and perisher is inner and the densest is the same thing
Answer: They both described the inner part
Explanation:
Why can u see the planets at night
Answer:
stupid question
Explanation:
A 1500 kg car traveling at 15m/s to the south collides with a 4500 kg truck that is initially at rest at a stoplight. the car and truck stick together and move together after the collision, what is the final velocity of the two vehicles
Answer: 3.75 m/s
Explanation:
Here's what you know: The car has mass 1500 kg, and initial velocity 15.0 m/s. The truck has mass 4500 kg and initial velocity 0 m/s. The final mass is 6000 kg (4500 kg plus 1500 kg, because they stick together) and we are looking for the final velocity. Using the formula p = mv, and the concept that p before equals p after, the p of the car plus p of the truck equals the p of them together. So, 1500 x 15 + 4500 x 0 = 6000 x v final. 22500 = 6000 v, and v = 3.75 m/s. The velocity is positive, and the initial velocity of the car was positive, so the two vehicles together are traveling to the south just like the car was initially.
Given a helicopter flying up and sideways at a velocity of 95 m/s at an angle of 35º to the ground, find the horizontal component of the velocity.
Answer:
The horizontal component of the velocity of the helicopter is approximately 77.82 m/s
Explanation:
The given parameters are;
The speed of the helicopter, v = 95 m/s
The angle in which the helicopter is flying = 35° to the ground
The horizontal component of the velocity is given by the component of the magnitude, R, of the velocity of the helicopter in the x-direction as follows;
[tex]v = \sqrt{v_x^2 + v_y^2}[/tex]
Where;
vₓ = v × cos(θ) = The horizontal component
[tex]v_y = v \times sin(\theta)[/tex] = The vertical component
∴ The horizontal component of the velocity, vₓ, of the helicopter with 95 m/s velocity moving at an angle of 35° to the horizontal is given as follos
vₓ = 95 × cos(35°) ≈ 77.82 m/s
The horizontal component of the velocity of the helicopter ≈ 77.82 m/s.
A person takes a ride to the top of a building in an elevator. If the elevator starts with
electrical energy, what types of energy does the electrical energy transform into during
this process? Put at least four answers.
Answer:
mechanical energy
Explanation:
Alok and his father are sitting at a distance of 5 meter on a seesaw. His father is at the distance of 2 meter from the fulcrum and Slok weighs 20 kg. If they are balancing the seesaw, find the weight of his father.
Answer:
30kg
Explanation:
Distance between Alok and father = 5m
Father's distance from fulcrum = 2m
Solak's weight = 20kg
Unknown:
Weight of the father = ?
Solution:
This problem entail the balancing of forces around a fulcrum.
In this problem;
workdone by father = workdone by Alok
( mass x distance) father = (mass x distance) Alok
distance of Alok from the fulcrum = 3m
Input the parameters and solve;
mass of father x 2 = 20 x 3
mass of father = 30kg
The weight of the father is 30kg
Old thermometers contained very small amounts of mercury. The mercury in the photo has a melting point of −38.8 °C. What can you conclude about the melting point of the mercury in old thermometers?
A. Its melting point can only be determined when the mercury is burned.
B. Its melting point changes as the mercury’s temperature changes.
C. Its melting point equals −38.8 °C because it is mercury.
D. Its melting point is less than −38.8 °C because its volume is smaller.
Answer:
C. Its melting point equals −38.8 °C because it is mercury.
Explanation:
Given that the old thermometer contained a very small amount of mercury and the melting point of mercury is [tex]-30^{\circ}C[/tex].
The temperature at which any material starts changing from the solid-state to the liquid-state is known as the melting point of the material.
As the melting point of any material does not depends on the amount of material. So, whether there is a small amount of mercury or is a large amount of mercury.
Hence, the melting point remains [tex]-30^{\circ}C[/tex] because it is mercury.
So, option (C) is correct.
As per the definition above, there is no need to burn the mercury to determine the melting point, so option (A) is wrong.
The melting point does not depend on the initial temperature, mass, volume of the material, so options (B) and (D) are wrong.
Typically in hot weather or when a person’s muscles heat up, a person can produce more________ than normal. IT’S P.E WORK!
Answer:
Sweat. Hope this helps!!
Explanation:
Which has more inertia, a car with a mass of 900kg or a car with a mass of 1,500kg. Explain your answer.
Answer:
Which has more inertia - a car with a mass of 900kg or a car with a mass of 1500kg - explain. The bigger the mass - the larger the inertia but you need to exert more force to start the movement.
Explanation:
A Parachutist with a camera, with descending at a speed of 12.5m/s, releases, the camera at an altitude of 64.3m. What is the magnitude of the velocity of the camera just before it hits the ground ? The acceleration of gravity is 9.8 m/s and air friction is negligible. How long does it take the camera to reach the ground
Given :
Initial velocity, u = 12.5 m/s.
Height of camera, h = 64.3 m.
Acceleration due to gravity, g = 9.8 m/s².
To Find :
How long does it take the camera to reach the ground.
Solution :
By equation of motion :
[tex]h = ut+\dfrac{gt^2}{2}[/tex]
Putting all given values, we get :
[tex]12.5t+\dfrac{9.8t^2}{2}=64.3\\\\4.9t^2+12.5t=64.3[/tex]
t = 2.56 and t = −5.116.
Since, time cannot be negative.
t = 2.56 s.
Therefore, time taken is 2.56 s.
Hence, this is the required solution.
A mover applies a net force of 28 N to a sofa that has a mass of 70 kg.
What will the sofa's acceleration be?
Answer: .4 m/s^2= acceleration
Explanation:
f = m*a
We can rearrange this equation to solve for acceleration. Therefore,
a=f/m
a= 28N/70kg
a= 0.4 m/s^2
A person of 45 kg can accelerate at 1.5 m/s on a straight road. What is the force created?
Answer:
The answer is 67.5 NExplanation:
The force acting on an object can be found by using the formula
Force = mass × accelerationFrom the question
mass = 45 kg
acceleration = 1.5 m/s²
We have
Force = 45 × 1.5
We have the final answer as
67.5 NHope this helps you
conversion
18230 mJ to kJ?
Answer:
0.01823
Explanation:
big brain
If a truck has a mass of 100 kg and
a velocity of 35 m/s, what is its
momentum?
Brainliest ASAP!!
Solve the equation 4(s+5)=60
Answer:
s=10
Explanation:
4(s+5)=60
4s+20=60
4s=40
s=10
What is the meaning of disgust?
Answer:
Disliking something
Explanation:
For an example : Ah you disgust me
Answer:
Strongly disproval of something (usual this something is gross)
"Profound dislike or annoyance caused by something sickening or offensive." - The Free Dictionary
Explanation:
Example: Her attitude filled me with disgust
Example 2: Your gross remarks disgust me.
If you were to travel from the equator to the higher latitudes (near either pole) on Saturn, the differential rotation would cause the length of a day that you would measure to be longer by ____ hour(s). [Number accurate to 2 places after the decimal.]
Answer:
Saturn's differential rotation will cause the length of a day measures to be longer by 0.4 hours
Explanation:
Differential rotation occurs due to the difference in angular velocities of an object as we move along the latitude of the or as we move into different depth of the object, indicating the observed object is in a fluid form
Saturn made almost completely of gas and has differential motion given as follows
Rotation at the equator = 10 hours 14 minutes
Rotation at high altitude = 10 hours 38 minutes
Therefore;
The differential rotation = 10 hours 38 minutes - 10 hours 14 minutes
The differential rotation = 24 minutes = 24 minutes × 1 hour/(60 minutes) = 0.4 hours
The differential rotation = 0.4 hours
Therefore, the measured day at the higher altitude will be 0.4 longer than at the equator.
how many seconds are there in 3 days and 36 hours
The answer is 388 800 sec
Answer:
388800 secs
Explanation:
1 day = 24 hrs
so 24 times 3 = 72
and 1 hour is equal to 60 min
108 x 60 = 6480
and 60 secs in a minute
6480 x 60= 388800
Elements are arranged in the periodic table based on various patterns. For example, elements found in the rows near the top
A
have higher atomic numbers than the elements in the rows near the bottom
В.
all have the same atomic number.
C.
have lower atomic numbers than the elements in the rows near the bottom.
D. have the same atomic numbers as the elements in the rows near the bottom.
What is the relationship between the tilt of the Earth on its axis, latitude, and temperature?
Answer:
The combination of more direct rays of sunlight and more hours of daylight causes the hemisphere tilted toward the sun to receive more solar radiation and to have warmer temperatures. When the Northern Hemisphere is tilted toward the sun, latitudes between the equator and 90°N (the North Pole) are experiencing summer.
Hope this helps :) :) :)
What is the acceleration of a car moving in a straight line that increases from 0m/s to 50 m/s in 5 seconds?
Answer:
10m/s^2
Explanation:
a=change in velocity/change in time
50/5=10m/s^2
Which of the following solar oven design materials would serve to conduct heat to maximize thermal energy in the s'more?
1. metal platform
2. foil on the exterior flap
3. layers of cotton lining the interior
4. white paper lining the interior
Answer:
The correct option is;
3. layers of cotton lining the interior
Explanation:
In the procedure for making a solar oven it is essential place the inside portion of the carboard flap be made that the air made hot by the heat of the Sun does is not removed from the oven as convection current, and to provide insulation that limits heat loss by thermal radiation as well as conduction to cooler surfaces.
Answer:
^
Explanation: