Which requires more work: stretching a strong spring a certain distance or stretching a weak spring the same distance? Defend your answer. **More force** is required to stretch the strong spring, so more work is done in stretching it the same distance as a weaker spring.

- Which requires more work :
**stretching a strong spring a certain distance or stretching a weak spring the same distance? More force is required to stretch the string spring**, so more work is done in stretching the same distance as a weaker spring

Contents

- 1 Why is it easier to stop a lightly loaded truck then a heavier one that has equal speed?
- 2 Why do you do no work on a 25kg backpack when you walk a horizontal distance of 100m?
- 3 What is the ΔKE for an airplane that is moved 500 m in takeoff by a sustained force of 5000 N?
- 4 Which requires more work stretching a strong spring a certain distance or stretching a weak spring the same distance defend your Answe?
- 5 Is work equal to power?
- 6 Why is there no work in carrying a 9 kg backpack as you walk a horizontal distance of 12 m?
- 7 Why does the force of gravity do work on a car that rolls down a hill?
- 8 Why bother using a machine if it Cannot multiply work input to achieve greater work output?
- 9 What is the force that accelerates a rocket into outer space?
- 10 Which has the greater momentum when moving which has the greater momentum when moving?
- 11 How much work is done when you push a crate horizontally with 100 newtons across a 10 meter factory floor?
- 12 How do you calculate work?
- 13 When you are working you are exerting?

## Why is it easier to stop a lightly loaded truck then a heavier one that has equal speed?

It is easier to stop a lightly loaded truck than a heavier one moving at the same speed because it has less KE and will therefore require less work to stop. (An answer in terms of impulse and momentum is also acceptable.)

## Why do you do no work on a 25kg backpack when you walk a horizontal distance of 100m?

Why do you do no work on a 25 kg backpack when you walk a horizontal distance of 100 m? You do no work because the backpack moves relative to you. Although no work is done on the wall, work is nevertheless done on internal parts of your body. Two people who weigh the same climb a flight of stairs.

## What is the ΔKE for an airplane that is moved 500 m in takeoff by a sustained force of 5000 N?

From W = ΔKE, ΔKE = Fd = (5000 N)(500 m) = 2,500,000 J.

## Which requires more work stretching a strong spring a certain distance or stretching a weak spring the same distance defend your Answe?

Which requires more work: stretching a strong spring a certain distance or stretching a weak spring the same distance? Defend your answer. More force is required to stretch the strong spring, so more work is done in stretching it the same distance as a weaker spring.

## Is work equal to power?

As is implied by the equation for power, a unit of power is equivalent to a unit of work divided by a unit of time. Thus, a Watt is equivalent to a Joule/second. Thus, the power of a machine is the work/time ratio for that particular machine. A car engine is an example of a machine that is given a power rating.

## Why is there no work in carrying a 9 kg backpack as you walk a horizontal distance of 12 m?

The object must move a distance in the same direction as the force you apply to it. The force you are applying is upwards. Since the backpack does not move upward as you walk horizontally you do no work on the object. You are not doing work since you are not apply a force on the backpack over a distance.

## Why does the force of gravity do work on a car that rolls down a hill?

Why does the force of gravity do work on a car that rolls down a hill but no work when it rolls along a level part of the road? Gravity pushes the car toward the ground. So, when it is on a hill it moves down. When the ball is on a level road gravity does no work because the car can not go downward on a level surface.

## Why bother using a machine if it Cannot multiply work input to achieve greater work output?

Why bother using a machine if it cannot multiply work input to achieve greater work output? It can make work easier, because you do not need to use as much power.

## What is the force that accelerates a rocket into outer space?

The two forces acting on rockets at the moment of launch are the thrust upwards and the weight downwards. Weight is the force due to gravity and is calculated (at the Earth’s surface) by multiplying the mass (kilograms) by 9.8.

## Which has the greater momentum when moving which has the greater momentum when moving?

The forward moving object will have the greatest momentum. An object with a changing speed will have a changing momentum.

## How much work is done when you push a crate horizontally with 100 newtons across a 10 meter factory floor?

If you push a crate horizontally with 100N across a 10m floor and the friction between the crate and floor is a steady 70N, how much kinetic energy does the crate gain? 12. ΔKE = work done = (100 N – 70 N)(10 m) = (30 N)(10 m) = 300 Nm = 300 J.

## How do you calculate work?

Work can be calculated with the equation: Work = Force × Distance. The SI unit for work is the joule (J), or Newton • meter (N • m). One joule equals the amount of work that is done when 1 N of force moves an object over a distance of 1 m.

## When you are working you are exerting?

Terms in this set (70) When do you work? When you exert a force in an object that causes the object to move some distance in the same direction as the exerted force.