Work and Energy Practice 2
10 problems · instant feedback · full explanations
The work-energy theorem: net work equals change in kinetic energy. Track energy transformations — work in, kinetic out, potential stored — and the books always balance.
Q1.
How much work does gravity do on a suitcase pushed horizontally across a level floor?
Multiple choice · Easy
Q2.
How much work is done lifting a 10 kg box 3 m vertically at constant speed? (Use g = 9.8 m/s².)
Numerical answer (J) · Easy
Q3.
A spring with k = 200 N/m is stretched 0.1 m. How much elastic potential energy is stored?
Numerical answer (J) · Medium
Q4.
A 500 W heater runs for 10 s. How much energy does it deliver?
Multiple choice · Easy
Q5.
A 1000 kg car braking from 20 m/s to rest: how much energy must the brakes dissipate? (J)
Numerical answer (J) · Medium
Q6.
Negative work means:
Multiple choice · Easy
Q7.
Work is a vector quantity.
True / False · Easy
Q8.
Doubling an object's speed quadruples its kinetic energy.
True / False · Medium
Q9.
A 0.5 kg pendulum bob on a 2 m string is released from 60° to the vertical. What is its speed at the bottom? (Use g = 9.8 m/s².)
Numerical answer (m/s) · Hard
Q10.
Which of these is a conservative force?
Multiple choice · Medium