Name _______________________________________ Date ___________________________ Period ________
Momentum
Instructions: There are three parts to each of the 10 problems below. Part B is more challenging than part A and
part C is more challenging than part B. You should definitely be able to do part A in all 10 problems. Try part B for
each one and go on to part C if you can do part B. Don't assume that you can't do one without reading it because
there are different kinds of questions.
1. The Shinkansen, Japan's high speed "bullet train", consists of several different versions of trains that
have been in service since 1963. The 100-series trains consist of 16 cars that have a combined mass of
925,000 kg. The top speed of a typical 100-series train is 220 km/h.
a. What is the momentum of one of these trains?
b. What is the momentum in kg·m/s?
c. How far would the train travel in 22 minutes?
2. The 300-series Shinkansen trains consist of 16 aluminum cars with a combined mass of 710,000 kg.
The reduction in mass from the 100-series enables the 300-series trains to reach top speed 270 km/h.
a. What is the momentum of one of these trains at top speed?
b. What is the difference in momentum between the 100-series and 300-series trains traveling
at top speed?
c. Would the 300-series train be going faster or slower if its mass was 7.10 x 105? How much?
3. The largest animal ever to have lived on the Earth is the blue whale. Consider a blue whale with a
mass of 146,000 kg and a top swimming speed of 24 km/h.
a. What is the momentum of this whale at this speed?
b. What is the momentum of the whale in kg·m/s?
c. Assume the whale's cruising speed is 17 km/h. What percentage is this of the whale at top
speed?
4. In 1996, Michael Johnson ran 200.0 m in 19.32 s. Johnson's mass at the time of his record breaking
run was 77 kg.
a. What was his average speed?
b. What was his momentum at average speed?
c. Let's assume that Michael Johnson gained 4 kg and in 1997 was able to run at the same speed
as the previous year and mass. What would be his momentum in 1997?
5. Although it cannot sustain its top speed for more than 8.65 s, the cheetah can run a distance of .274
km during that time.
a. What is the cheetah's top speed?
b. What is the cheetah's top speed in m/s?
c. What is the cheetah's momentum at top speed in both kg·km/s and kg·m/s?
6. The highest land speed for a rail-guided vehicle was set in 1982 by a rocket sled at Holloman Air Force
Base, in southern New Mexico. The sled was unmanned, but if it had a payload with a mass of 25 kg, the
payload's momentum would have been about 68,000 kg·m/s.
a. What was the speed of the of the payload and sled in m/s?
b. What was the speed of the payload and sled in km/h?
c. Suppose we could increase the momentum of the sled to 7.8 x 10 4 kg·m/s without changing its
mass. How fast would it be traveling now in m/s?
7. The largest species of hummingbird is the Patagonia gigas, or the giant hummingbird of the Andes.
The bird has a length of 21 cm and can fly at a top speed of 11.1 m/s. Suppose one of these
hummingbird flies at top speed.
a. If its momentum is 0.278 kg·m/s, what is the hummingbird's mass?
b. What would its momentum be in kg·km/h?
c. How long would it take to travel 1000 times its length?
8. A hovercraft, also known as an air cushion vehicle, glides on a cushion of air, allowing it to travel with
equal ease over water or land. The first commercial hovercraft to cross the English Channel, the V. A-3,
had an average speed of 27 m/s. Its momentum at this speed was 48,000 kg·m/s.
a. What was the mass of the V. A-3?
b. How fast was it traveling in km/h?
c. What would be the mass of the vehicle if the momentum was 4.8 x 105 kg·m/s?
9. A student with a mass of 55.0 kg rides a bicycle at a speed of 5.0 m/s. The momentum of the bicycle
and the rider equals 320 kg·m/s.
a. What is the combined mass of the student and the bicycle?
b. What is the mass of the bicycle?
c. How fast would the bicycle alone have to move in order to have the same momentum as that
of the student and the bicycle together?
10. The S.S. Norway is a passenger ship with a mass of 69,000,000 kg and a top cruising speed of
33 km/h.
a. What is the momentum of the S.S. Norway once it has reached its top cruising speed?
b. What is the momentum in kg·m/s?
c. Would the momentum of the ship be more or less if the mass were 6.9 x 10 8 kg? What would
it be in kg·km/h?