Download PSCI 103

Problems:
1)
The following data was obtained by measuring the mass and volume of 5 samples of a
mineral.
Calculate the total mass and total volume for the samples as you did in the laboratory.
Draw a best-fit graph to determine the average density of the material.
Sample
1
2
3
4
5
Mass (g)
46.75
37.34
59.10
61.94
47.82
Volume (mL)
9.0
7.3
11.9
12.0
9.4
Total Mass (g)
46.75
Total Volume
(mL)
9.0
2)
Using your graph, if you have a 100.00 g sample of the mineral, what volume would it
occupy?
3)
If you had a have a 40.0 mL sample of the mineral what is the mass of this sample?
4)
What is the volume of a rectangular solid that is 8.6 mm x 15.0 mm x 59.6 mm?
In mm3, cm3, and m3. Express your answer in correct significant figures and in scientific
notation.
5)
How many pieces of rice that are 1.4 mm x 8.2 mm x 1.4 mm would fit into a cylinder that
measures 28.54 cm high and has a diameter of 7.26 cm? Express your answer in correct
significant figures and in scientific notation.
6)
If a car is traveling at 110 km/hr and it travels for 45 minutes how far does it go?
7)
If a truck travels 540 km in 6.5 hrs, what is its average speed?
8)
Consider the following scenario. A car (and driver) are traveling down Rt. 95 at 55 mph. The
driver increases its speed to 70 mph to pass a truck. A police car spots the car speeding, and
pulls the car over to the side of the road to a complete stop. Construct a graph illustrating the
speed and acceleration for this car.
9)
Two students are conducting an experiment to determine the height of a building. One
student at the top drops a rock. The second student times how long it takes the rock to fall to
the ground. Ignoring air resistance, how high is the building if it takes 4.5 seconds for the rock
to fall from the top of the building. (d = ½at2)
10)
What is the speed of the rock when it hits the ground?
11)
If a ball rolls down a ramp that is 1.750m long and it takes 2.48s to do so: a) what is
the acceleration of the ball and b) what is the speed of the ball at the end of the
ramp?
12)
How much work is done to place a 10.00 kg bag of dog food on a shelf 1.500 meters high?
13)
A 62.6 kg woman ran up a flight of stairs that is 3.28 m high in 1.70s: a) what is her
weight, b) how much work did she do and c) how many watts of power were exerted?
14)
If you use 1750 J of energy to run up a flight of stairs, how many flights would it take to equal
the energy of a snickers bar that has 245 Calories?
15)
If a 25.64 g bob of a pendulum is raised 22.0 cm and let go. What is the gravitational potential
energy of the bob at the top.
16)
Explain using all of Newton’s laws why a shopping cart is harder to push as it fills with
groceries?
17)
A feather and a rock do not fall at the same rate when dropped. Provide a scientific
explanation.
18)
Running and walking up a flight of stairs requires the same amount of work, but require
different power. Why is this so?
19)
A car traveling at a constant speed of 65 mph has zero acceleration. Explain.
20)
Explain (using Newton’s Laws) how an outboard motor propels a motor boat forward.
21)
Each week I fill my gas tank so I can drive to school. List as many forms of energy that occur
within an automobile. Identify, if you can, the object that converts one form of energy to
another. Such as a turn signal converting electrical energy to radiant energy.
22)
Using a toy car, ramp, meterstick, stopwatch, and balance:
a. Calculate the potential energy of the car at the top of the ramp.
b. Determine the final velocity of the car at the bottom of the ramp.
c. Determine the kinetic energy of the car at the bottom of the ramp.
d. The average acceleration of the car down the ramp.
e. The force required to accelerate the car down the ramp.
f. The amount of energy "lost".
g. Account for the "lost" energy, how do you account for it being "lost"?
h. The efficiency of the car in converting potential energy into kinetic energy.
Data Table
Mass of car: 50.00 g
Time (Trial 1) 2.30 s
Height of Ramp: 20.00
cm
(Trial 2) 2.45 s
Length of Ramp: 1.80 m
(Trial 3) 2.40 s
23)
A toy car with a mass of 25.0 grams is sitting on the top of an inclined plane. The inclined
plane is 1.80 meters long and 25.0 cm high at one end. What is the gravitational potential
energy of the car at the top of the ramp?
24)
When the car in the above problem was allowed to roll down the ramp, a student determined
that it required 1.90 seconds to reach the end of the ramp. What is the kinetic energy of the
car at the bottom of the ramp using the student's data?
25)
Explain why a magician is able to pull a tablecloth out from under a dining set complete with
candle holders.
26)
Assuming that a red car has a mass of 1000 kg and a white car has a mass of 2000 kg. If both
cars are traveling at the same velocity, which car has the greater kinetic energy?
27)
Assume that a red car has a mass of 1000kg and a white car has a mass of 2000 kg. If the red
car has twice the velocity of the white car, which car has the greater kinetic energy?
28)
A car moves 4 times as fast as another identical car. Compared to the slower car, how much
more kinetic energy does the faster car have than the slower car?
29)
When the same net force is applied to two blocks, the yellow one has a larger acceleration
than the blue one. Explain.
30)
Determine the amount of work required for a 85-kg person to climb one flight of stairs (2.5 m)
in 1.2 seconds.
31)
Determine the power exerted in the previous problem.
32)
Determine the number of flights the person will need to climb in order to "burn" off a Pepsi
that contains 250 Calories.
33)
Using all of Newton’s Laws of Motion, compare the motion of the solid and plastic bowling
balls when struck by the mallet.
34)
What was dropped on the moon by the Apollo 15 astronauts?
What happened?
What did this prove?
36)
Calculate your weight?
37)
A car is traveling at a constant speed of 65 mph along Route 95 toward Boston from
Providence. The car reaches a work zone and slows to 40 mph. After it passes through the
work zone it resumes its speed of 65 mph. Draw two graphs, labeling the axes, that illustrate
the speed and acceleration of the car.