Name: _______________________________
Momentum of Individual Objects – Notes
1. Ballistic Pendulum
A. Draw the diagram of the ballistic pendulum.
B. Write the conservation of momentum equation for the ballistic pendulum.
C. Write the conservation of energy equation for the ballistic pendulum.
D. Why is it better to measure the x-displacement of the pendulum rather than h?
E. What is the equation for v’ in terms of h and then in terms of x (with the small angle
approximation?)
F. How much of the original kinetic energy of the bullet was converted to heat?
2. Impulse
A. Integral equation of impulse (use J,notI )
B. Favg =
C. A typical impact time for a ball hitting the floor is _______________.
3. Rockets
A. If 4 kg/s of tomatoes were thrown onto a bathroom scale with a speed of 5 m/s, what
will the scale read on average?
B. If 4 kg/s of elastic superballs were thrown onto a bathroom scale with a speed of 5
m/s, what will the scale read on average?
C. Hot gases coming from the end of a rocket produces a forces called ______________.
D. For the Saturn rockets that took the Apollo astronauts to the Moon:
i. u =
ii. dm/dt =
iii. FThrust =
E. What is the “rocket equation”?
F. What is the final velocity minus the initial velocity of the rocket with gravity?