Potential Energy
Which person has the highest GPE?
Mr Joel on a diving board 20 m above ground
Ms T on a diving board 20 m above ground
Ms T
A 1200 kg car is travelling at 15 m/s
Calculate the kinetic energy of the car.
135000 J
A 20 N horizontal force pushes a box through a distance of 5.0 m in the same direction as the force.
Calculate the work done by the force.
100 J
Find the unit for PE using the formula mgh (the answer is not Joules)
kg*m2/s2
A 0.50 kg ball and a 2.0 kg ball are travelling at the same speed. The 0.50 kg ball has a kinetic energy of 18 J.
What is the kinetic energy of the 2.0 kg ball?
72 J
Ziyou pulls a 10 kg suitcase with a force of 40 N at an angle of 30∘ above the horizontal. The suitcase moves 8.0 m horizontally.
Calculate the work done by the pulling force.
277 J
A 60 kg student climbs a staircase with a vertical height of 8.0 m.
Calculate the increase in the student's gravitational potential energy.
4700 J
A 1500 kg car increases its speed from 10 m/s to 30 m/s.
By what factor does its kinetic energy increase?
9
A 5.0 kg box is pushed 12 m along a horizontal floor by a constant 30N force. A frictional force of 8.0 N acts opposite to the motion.
Calculate the net work done on the box.
264 J
A 0.50 kg ball is dropped from a height of 12 m. Air resistance is negligible.
Calculate the speed of the ball just before it reaches the ground.
15.3 m/s
A 2000 kg car is travelling at 25 m/s. The driver applies the brakes and the car comes to rest.
Calculate the average braking force if the car travels 50 m while stopping.
12500 N
A 2.0 kg object is pulled 6.0 m up a frictionless inclined plane at an angle of 25∘ to the horizontal by a constant force of 30 N parallel to the slope.
Calculate the net work done on the object.
130 J
A 1000 kg car travels down a hill from a height of 40 m with an initial speed of 10 m/s. The amount of energy dissipated by friction and air resistance during the journey is 154 kJ.
Calculate the speed of the car at the bottom of the hill.
24 m/s
A 1200 kg car travels down a mountain road from a height of 80 m to 20m. Its speed increases from 12 m/s to 30 m/s.
Calculate the energy dissipated by friction and air resistance during the journey.
252 kJ
A 1000 kg car travelling at 30 m/s collides with a 1500 kg car initially at rest. After the collision, the two cars move together.
Calculate the amount of the initial kinetic energy that is lost in the collision.
270 kJ
A 4.0 kg block is initially at rest on a horizontal surface. A variable force acts in the direction of motion. The force increases uniformly from 0 N to 20 N over a distance of 10 m. A constant frictional force of 4.0 N opposes the motion.
Calculate the final speed of the block.
5.48 m/s
A 0.20 kg ball is travelling horizontally at 12 m/s when it strikes a stationary 0.80 kg block. The ball becomes embedded in the block, and the combined objects then slide up a frictionless 20∘ slope.
Calculate the distance travelled by the combined objects from the point of collision to the point where the combined objects reach maximum height.
0.322 m
A 2.0 kg block is pushed from rest up a 30∘ frictionless inclined plane by a constant 25 N force parallel to the slope. The block travels 4.0 m.
Calculate the speed of the block after travelling 4.0 m.
7.8 m/s