How is a joule defined? (1 point)
• It is the work done when a force of 1 newton is applied to an object for a distance of 1 meter.
• It is the force needed to make an object with a mass of 1 kilogram travel 1 meter.
• It is the force needed to make an object with a mass of 1 kilogram accelerate by 1 kilogram per second squared.
• It is the work done when a force of 1 newton is applied to accelerate an object by 1 kilogram per second squared.
• It is the work done when a force of 1 newton is applied to an object for a distance of 1 meter.
A soccer player kicks a ball, applying a force of 1,000 newtons over a distance of 0.2 meter. The ball travels 50 meters down the field before another player stops the ball. How much work was done during the kick? (1 point)
• 200 joules
• 5,000 joules
• 50,000 joules
• 10 joules
To calculate work done, we use the formula:
Work (W) = Force (F) x Distance (d)
Given:
Force (F) = 1,000 newtons
Distance (d) = 0.2 meter
Work = 1,000 newtons x 0.2 meters
Work = 200 joules
Therefore, the correct answer is:
• 200 joules
A person raises a box with a weight of 50 newtons by 0.5 meter. How much work does the person do in this action? (1 point)
• 25 joules
• 0.0 joules
• 100 joules
• 0.01 joule
To calculate the work done in lifting the box, we use the formula:
Work (W) = Force (F) x Distance (d)
Given:
Force (F) = 50 newtons
Distance (d) = 0.5 meters
Work = 50 newtons x 0.5 meters
Work = 25 joules
Therefore, the correct answer is:
• 25 joules
A person gets a running start toward a wall from 5 meters away. The person pushes the wall with a force of 500 newtons, but the wall does not move. How much work is done by the person? (1 point)
• 100 joules
• 2,500 joules
• 0 joules
• 0.01 joule
When the wall does not move, no work is done by the person. In order to do work, the force applied must cause displacement. Therefore, the correct answer is:
• 0 joules