Kibala
CP Physics
Conservation of Energy Problems 2
Complete on a piece of notebook paper. All problems require diagrams
labeled with types of energy present at each important location. Then
calculations.
𝐾𝐸 = 1⁄2 𝑚𝑣 2
𝐺𝑃𝐸 = 𝑚𝑔ℎ
𝐸𝑃𝐸 = 1⁄2 𝑘𝑥 2
1) A circus uses a spring-loaded cannon to launch a 70 kg clown
straight up into the air. If the spring constant is 150,000 N/m and
it is compressed 1.1 meters, how high does he go?
2) The bleachers outside are 6.67 meters above the ground. If an
object is dropped off of the top of the bleachers calculate the
velocity it hits the ground with?
3) In a wild shot, Bo flings a pool ball of mass m off a .68 m high pool
table, and the ball hits the floor with a speed of 6 m/s. How fast
was the ball moving when it left the pool table?
4) Frank, a San Francisco hot dog vendor, has fallen asleep on the
job. When an earthquake strikes, his 300 kg hot dog cart rolls
down Nob Hill and reaches point A at a speed of 8 m/s. How fast
is the hot dog cart going at point B when Frank finally wakes up
and starts to run after it?
Kibala
CP Physics
5) The women’s pole vault record as of Spring 1997 was a height of
4.55 m, set by Emma George. What do you estimate was Emma’s
speed prior to planting the pole?
6) A bow and arrow is fired by a magician to knock and apple off of
the head of an audience member. The arrow is fired perfectly
horizontally and drops very little during its path to the apple. The
bow has a spring stiffness constant of 8900 N/m. The 16 kg arrow
requires a speed of 15 m/s to knock the apple of the participant’s
head then how far back should the magician pull back his bow?
7) James fired a dart gun in the hallway at the top of the lockers 2
meters above the ground. He compresses the spring in the gun 4
cm with a 55 gram dart. The spring in the dart gun has a spring
constant of 200 N/m.
a. With what velocity does the dart leave the gun?
b. With what velocity does the dart gun hit the ground?
Giancoli 36,43, skateboarder