Exam Review – The Sequel
1. The following velocity-time graph represents the motion
of two vehicles.
velocity (m/s [W])
(a) During what time interval were both vehicles traveling
in the same direction?
(b) During what time interval were both vehicles traveling
with the same velocity?
(c) Describe the motion of each vehicle from
0s to 10s. (Clearly indicate when any changes in motion occur)
(d) Determine the acceleration of each vehicle between
0s and 3.5s.
(e) How far apart are the vehicles after the first
3.5 s of motion? (show all your work)
40
30
20
10
0
- 10
1 2 3 4 5 6 7 8 9 10
Time (s)
0
-20
-30
6
2. A sprinter who is competing in a 100-m race accelerates from rest to a top speed of 10.0 m/s over a distance of
15 m. The remainder of the race is run at a constant speed.
(a) What length of time is required for the sprinter to reach top speed?
(b) What is the sprinter's time for the entire race?
(c) What is the sprinter's acceleration?
3. A ball is thrown vertically upwards with an initial velocity of 3.5 m/s from a window that is 3.6 m above the ground.
Determine the maximum height of the ball above the ground. (4.2 m)
4. A 85 kg football player kicks a 410 g football giving it an velocity of 240 m/s after 0.10 s.
(a) Determine the magnitude and direction of action and reaction forces in this situation. (984 N)
(b) How far does the football move in the 0.10 s time interval? (12 m)
5. A 0.50 kg shuffle board disk accelerates from rest at 8.0 m/s2 under an applied force of 7.0 N [F]. Determine the
force of friction acting on the disk and the coefficient of friction between the shuffleboard and the disk. (3.0 N, 0.61)
6. A 2.0 kg bag is held by a string that is attached to the ceiling as shown in the diagram below. An 11 g bullet
travelling at 86 m/s strikes the stationary bag. Determine the maximum height of the bag and bullet after the
collision. (2.1 m)
7.
Sheila was helping her uncle move pianos. She used a 3.0 m long ramp to move a 230 kg piano 1.3 m upwards into
a delivery truck. Sheila exerted a force of a force of 1020 N throughout the length of the ramp to push the piano into
the truck. What was the overall efficiency of the ramp? (96%)
8. A blacksmith heated an iron horseshoe to a temperature of 450oC to make it more malleable. He then placed the
0.45 kg horseshoe in a bucket containing 8.0 kg of water at 21oC. What maximum temperature will the water reach
after the addition of the horseshoe? (24oC)
9. Tom was out ice fishing when his snowmobile keys fell into the lake. They became frozen into a 3.5 kg block of ice. How
long would it take Tom to heat the ice from -21oC to 5.0oC with a 1750 W hair dryer? (810 s)
10. A formula one racing car is moving at mach 0.160 at a race track where the ambient air temperature is 20.0 oC.
(a) What is the speed of the car in km/h? (198 km/h)
(b) If the driver sounds the car’s horn (215 Hz) what frequency will an observer hear just ahead of the car? (256 Hz)
11. A 440 Hz tuning fork is used with a tube closed at one end to determine the speed of sound in helium gas. If the
spacing between the 1st and 3rd harmonic is 110 cm, what is the speed of sound in helium gas? Use a diagram in
your solution. (970 m/s)