Unit 3: Work, Energy and Power

The work done by a variable force F(x) = 3x² from x = 0 to x = 2 m is:

A 1000 kg car accelerates from 0 to 20 m/s in 10 s. What is the average power output in kW?

A force [math] N acts on an object. The work done moving it from x = 1 m to x = 4 m is

A spring has a force-displacement relationship [math]. The potential energy stored when compressed by distance d is

The work done by a variable force [math] from x = 0 to x = 5 m is

A 1 kg particle moves under the potential [math]. The equilibrium positions are at x =

The power delivered to a 4 kg object with velocity [math] by the net force is

A conservative force has potential energy [math]. The force as a function of x is

A force [math] N acts on a particle moving from (0,0) to (2,3). The work done along the path y = (3/2)x is

The potential energy of a spring is [math]. The force exerted by the spring is found by

A 3 kg mass slides down a frictionless curve described by [math] from x = 0 to x = 2. Its speed at x = 2 is (g = 10 m/s²)

A particle moves from x = 0 to x = 3 under [math] N. The work done is

The potential energy function [math] has stable equilibrium at x =

A 0.5 kg ball is dropped from a height of 20 m. What is its speed just before hitting the ground? (g = 10 m/s²)

A motor does 3000 J of work in 6 seconds. What is the power output?

A 3 kg object initially at rest is pushed by a net force doing 150 J of work. What is its final speed?

A spring with k = 200 N/m is compressed 0.1 m. What is the elastic potential energy stored?

The work done by a variable force F(x) as an object moves from x = a to x = b is:

A force of 100 N is applied at 60° to the horizontal to pull a box 5 m across the floor. How much work is done by this force?

Which of the following is a conservative force?

When friction decelerates a sliding box, the work done by friction is:

A machine requires 400 J of input energy to produce 300 J of useful output work. What is the efficiency?

The instantaneous power delivered by a force F to an object moving at velocity v is:

How much work is required to stretch a spring (k = 400 N/m) from 0.1 m to 0.3 m beyond its natural length?

On a potential energy vs. position graph, a stable equilibrium point is located at:

A 2 kg block slides down a 5 m frictionless ramp (height 3 m) then onto a rough horizontal surface (μ_k = 0.4). How far does it travel on the rough surface before stopping? (g = 10 m/s²)

A force acting on a particle is given by [math] (N). The work done by this force as the particle moves from [math] to [math] m is

A spring has a potential energy function [math] (Joules). The equilibrium positions are at

A force [math] acts on a particle that moves from the origin to [math]. Is this force conservative, and what is the work done along the straight-line path [math]?

A variable force [math] N acts on an object from [math] to [math]. The total work done is