Homework: 46, 48, 56, 58, 60, 66 (p. 233-235)
46. A bullet of mass 10g strikes a ballistic pendulum of mass 2kg. The
center of mass of the pendulum rises a vertical distance of 12 cm.
Assuming that the bullet remains embedded in the pendulum, calculate
th

3.4.2. Conservative Forces (gravitational and spring force)
and Potential Energy
The work done by a force F=F(x):
xf
xi
W F ( x)dx
xf
U -W xi F ( x)dx
a. Gravitational Potential Energy
U -W (mg)dy mg(y f yi )
yf
yi
At a certain height y:
U U U i mg(y yi )

Homework: 18, 52 (pages 190-193);
1, 4, 14, 15, 18, 20, 26, 33 (pages 229-233)
18. A block of mass m = 2.0 kg is dropped from height h = 40 cm
onto a spring of spring constant k = 1960 N/m. Find the maximum
distance the spring is compressed.
Gravitational

Homework: 41, 47, 52 (p. 134-135)
41. In the figure below, a car is driven at constant speed over a
circular hill and then into a circular valley with the same radius. At
the top of the hill, the normal force on the driver from the car seat
is 0. The driv

Homework: 1, 3, 8, 13, 18, 25, 28, 32, 43 (p. 159-162)
1. If a Saturn V rocket with an Apollo spacecraft attached had a
combined mass of 2.9 x 105 kg and reached a speed of 11.2 km/s,
how much kinetic energy would it then have?
v=11.2 km/s or v=11200 m/s