Physics I Final Exam Review
I. One and Two Dimensional Motion
1.) A car drives one lap around a 2.5 mile race track in a total time of 72 seconds.
a) What is the car’s average speed (mph)?
b) What is the car’s average velocity (mph)?
2.) A penny is dropped off a bridge into a river below and a splash is seen 4 and a half seconds later.
a) Determine the height of the bridge (ft).
b) What was the velocity of the penny just before it hit the water (mph)?
3.) During a soccer game, a ball is kicked straight up into the air with a speed of about 12 m/s.
a) How high up did it fly (m)?
b) How long was it in the air (s)?
4.) Shiela travels by car from one town to another. She drives for 30 minutes at 115 kph, and 12 minutes at 65 kph. She also spends 20 minutes stopping to pay for tolls and to get some snacks.
a) Determine the total distance traveled (km).
b) Determine the average speed for the trip (kph).
5.) A watermelon is dropped from an airplane traveling at an altitude of 4000 m. The watermelon has a terminal velocity of 68 m/s while in free-fall. How long was the watermelon in the air (seconds)?
6.) A train is traveling 48 mph to the east. If a person on the train is walking 3 mph west toward the back of the train, then:
a) what is the person’s velocity relative to the train (mag. and dir.)?
b) what is the person’s velocity relative to the ground (mag. and dir.)?
7.) A cargo plane traveling 122 km/hr parallel to the ground wishes to deliver a crate to a particular location by dropping the crate out a cargo door as it flies by the target. The plane must stay at a minimum altitude of 95 m from the ground. At what horizontal distance from the target must the plane release the crate?
8.) A boat wishes to travel from one dock to another on the opposite side of a river. The river is 120 m wide and the current flows at 3 m/s to the east. If the boat travels 10 m/s relative to the water, then what heading must the boat take if the dock is straight across the river?
9.) A motorcycle stunt driver jumps a length of junked cars from one ramp to another ramp. The driver leaves the 29 ramp and flies a horizontal distance of 20 m. What was the initial velocity of the cycle?
10.) If a ball is thrown off a 6 m ledge at an angle of 40° with an initial velocity of 18 m/s, then:
a) How high is the ball in the air at its highest point?
b) How long is it in the air?
c) How far does it travel horizontally?
II. Newton’s Laws of Motion
1.) a) State Newton’s First Law of Motion in full form
b) State Newton’s First Law of Motion in one word.
2.) State Newton’s Second Law of Motion.
3.) State Newton’s Third Law of Motion.
4.) If an object weighs 193 lbs. on Neptune, then what is its mass?
5.) Would a person weigh more in Denver or at the North Pole. Explain.
6.) A rope is used to horizontally pull a 90 kg pallet from rest to 3.5 m/s in a 5.0 s time span. How much tension does the rope withstand if the coefficient of kinetic friction is 0.5?
7.) If the coefficient of static friction between a 55 kg crate of cargo and a warehouse floor is 0.65, then what horizontal force is required to set the crate into motion?
8.) Calculate the support reaction force needed to keep the beam subjected to the forces shown below from breaking out of the wall (mag. and dir.).
y
F1 = 1000 N F2 = 800 N
63° 48°
x
25°
F3 = 400N
9.) A 1200 kg car skids with locked brakes down a 9 incline. The initial velocity of the car was 18 m/s and the coefficient of kinetic friction between the tires and the road is 0.70.
a) What is the magnitude of the normal force?
b) What is the magnitude of the acceleration of the car?
c) How far will the car skid before it comes to a stop?
III. Work, Power, and Mechanical Energy
1.) An object falls from rest on a ledge and crashes to the floor. If the object has a mass of 20 kg and the height of the ledge is 2.5 m, then:
a) how long does it take the object to fall to the ground?
b) how much PEg did the object have when it was on the ledge?
c) how much KE did the object have the moment before it hit the ground (how much energy did it deliver to the ground)?
2.) A 1.25-hp motor drives a hoist that can raise a load of 40-kg to a height of 15-m. At full power, how long will it take to raise the load?
3.) A rollercoaster climbs a large incline, then travels with a high speed for several more inclines.
Assume the coaster starts from rest at the top of the first hill. If the first incline is 42 m tall, and the second incline is 25 m tall, then:
a) how fast is the coaster going when they are at the bottom of the first incline?
b) how fast is the coaster going at the top of the second incline?
4.) Determine the min. force required by a person to push a 1250-kg car 80 m up a 7.0 incline if the coefficient of kinetic friction between the tires and the road is 0.40? The car starts at rest and reaches the top of the hill with a velocity of 1.1 m/s.
5.) An 0.8 kg object hanging from a 35 cm string is raised so that the string is parallel with the ground, then released from rest. What is the velocity of the object when the string makes a 20° angle with respect to the vertical?
IV. Momentum
1.) A kid and a scooter have a combined mass of 60-kg. If the kid is riding the scooter 6.0-m/s, and comes to a skidding halt, then how much time will pass before they come to rest? The coefficient of kinetic friction between the scooter’s tires and the ground is 0.50.
2.) A 125-g softball is struck by a bat with a force of 750-N. If the contact time between the ball and bat was 9-ms, then at what velocity did the ball leave the bat?
3.) A 32-g bullet strikes a 5.4-kg block of wood and embeds itself into the block. The block and bullet fly off together at 8.4-m/s. What was the incoming velocity of the bullet?
4.) An 1100-kg car traveling 13-m/s collides head-on with a 1300-kg car traveling 14-m/s in the opposite direction. The 1100-kg car comes to an abrupt rest immediately after the collision.
Determine the velocity of the 1300-kg car immediately after the collision.