Practice Final Exam 1
Physics 11
Problem 1
A student standing on the ground throws a ball straight up. The ball leaves the student's hand
with a speed of 15 m/s when the hand is 2.0 m above the ground.
a. For the ball’s entire motion, (i) draw a motion diagram and (ii) plot y, vy vs. t.
b. How long is the ball in the air before it hits the ground? (The student moves her hand out of
the way.)
Problem 2
A 500 kg piano is being lowered into position by a crane while two people steady it with ropes
pulling to the sides. Bob's rope pulls to the left, 15° below horizontal, with 500 N of tension.
Ellen's rope pulls toward the right, 25° below horizontal.
a. What tension must Ellen maintain in her rope to keep the piano descending vertically at
constant speed?
b. What is the tension in the vertical main cable supporting the piano?
Problem 3
A 200 g ball is dropped from a height of 2.0 m and bounces on a hard
floor. The force on the ball from the floor.
a. Draw an impulse-momentum bar diagram for the situation.
b. How fast is the ball moving after it bounces off the floor?
Hint: you need to find the velocity just before it hits the floor first.
Problem 4
A 20 kg child is on a swing that hangs from 3.0-m-long chains.
a. What is her speed at the bottom of the arc if she swings out to a 45° angle before reversing
direction?
b. Draw a picture of the situation and an energy bar diagram
Problem 5
0. 10 mol of argon gas is admitted to an evacuated 50 cm3 container at 20°C. The gas then
undergoes heating at constant volume to a temperature of 300°C.
a. What is the initial pressure in the container?
b. What is the final pressure of the gas?
Problem 6
A spotlight on a boat is 2.5 m above the water, and the light strikes the water at a point that is
8.0 m horizontally displaced from the spotlight. The depth of the water is 4.0 m.
a. Draw ray diagram for the situation.
b. Determine the distance d, which locates the point where the light strikes the bottom?
c. Did the light ray bend away or towards the normal? Explain your answer using short concise
sentences.
Problem 7
The owner of a van installs a rear-window diverging lens that has a focal length of 30 cm. When
the owner looks out through the lens at a person standing directly behind the van, the person
appears to be just 0.240 m from the back of the van, and appears to be 0.34 m tall.
a. How far from the van is the person actually standing?
b. How tall is the person?
c. Sketch a ray diagram of the situation.
Problem 8
In class, we saw a YouTube video of a woman while reaching for the gas pump ignited the
fumes.
a. How did the woman get electrically charged? Was she negative, positive or neutrally
charged? Explain your answer using short concise sentences.
b. Now use Coulomb’s law to explain how the fumes where ignited.
Problem 9
Use short concise sentences to answer the following questions using physics principles. Make
sure to explain your reasoning for each answer
a. Why does the apparent speed of light change as light enters water after coming in from air?
b. When you look through a microscope, an image is produced in order for you to see. (i)
Explain the image characteristics (type, size and magnification). (ii) What is the object
location relative to the focal point? (iii) Draw a ray diagram of the situation.
c. Explain in detail the type of lens is placed in front of the ruler?
Where is the object and where is it located?
d. (i) Why are the electrons in the outer shell of copper weakly
bound while the most inner electrons are tightly bound? (ii)
What is the difference between a conducting and insulating materials?
e. Plastic food wrap can be used to cover a container by stretching the material across the top
and pressing the overhanging material against the sides. (i) What makes it stick? (ii) Does
the food wrap stick to itself with equal tenacity? (iii) Does it work with metallic containers?
f. A high-voltage dc power line falls on a car, so the entire metal body of the car is at a
potential of 10,000 volts with respect to the ground. What happens to the occupants when
they are sitting in the car?