AP Physics C
Work and Energy Practice
1[65] A particle of mass m moves along the x axis. Its position varies with time
according to x = 2t3 – 4t2. Find (a) the velocity and the acceleration of the particle as
functions of t, (b) the power delivered to the particle as a function of t, and (c) the work
done by the net force from t=0 to t=t1.
2[66] A 3.0 kg particle starts from rest at x=0.05m and moves along the x axis under the
influence of a single force Fx = 6.0 + 4.0x -3.0x2. (a) Find the work done by the force as
the particle moves x=0.50m to x=3.0m. (b) Find the power delivered to the particle as it
passes through the point x = 3.0m.
3[67] The initial kinetic energy imparted to a 0.0200kg bullet is 1200J. (a) Assuming it
accelerated down a 1.00m long barrel, estimate the average power delivered to it
during the firing. (b) Neglecting air resistance, find the range of this projectile when it is
fired at an angle such that the range equals the maximum height attained.
4[68] The force Fx acting on a 0.500 kg particle is shown as a function of x in the figure
below. (a) From the graph, calculate the work done by the force when the particle
moves from x=0.0m to the following values of x: -4.00m, -3.00m, -2.00m, -1.00m, +1.00m,
+2.00m, +3.00m, and +4.00m. (b) If it starts with a velocity of 2.00 m/s along the +x axis,
how far will the particle go in that direction before stopping?