Phy 101
Exam #1
Practice Problems
1.) In our discussions on science and technology, the group decided that:
a.
b.
c.
d.
e.
There was no real difference between basic science and technology.
Society has had no effect on the development of technology.
Technology is the application of scientific discoveries to the needs of people.
Science is infallible; once a result is determined experimentally, it is never changed.
Because people have so much to do, they have not demanded technological advances to ease their work.
2.) In a classroom demonstration, a book and a piece of paper were dropped at the same time from the same
height. When the paper was flat, we observed that _________ and when the paper was rolled into a ball, we
saw that _______________.
a) both fell together, the paper landed first
b) the book landed first both times
c) the book landed first, the paper landed first
d) they both fell together both times
e) the book landed first, they both fell together
Answer the next questions by choosing the correct strobe photograph from those shown below. The strobe
illuminated the ball every 1/10 second.
a)
b)
c)
d)
e)
3.) Which of the above pictures shows the ball decelerating to a constant slow speed?
4.) Which of the above pictures shows what would happen to its speed of a wagon being pushed from rest to
speed and then stopped?
5.) Two student groups are in a tug-of-war contest with a 400 kg lawnmower. If the Habitat group has 6 people
pulling with 700 N each to the left and the College Students for Social Change group has 6 people pulling with
850 N each to the right, what is the lawn mower's acceleration?
a)
b)
c)
d)
e)
10 m/s2 toward the left
1.5 m/s2toward the right
3.0 m/s2toward the left
2.25 m/s2toward the right
0.75 m/s2toward the right
6.) A car stopped to turn the corner onto Spring Street and then accelerated for 8 seconds. If the car accelerated
at 0.3 m/s2, how far did it travel during its acceleration ?
a) 9.6 meters
b) 19.2 meters
c) 1.2 meters
d) 2.4 meters
e) 313.6 meters
7.)To do an experiment well, what different components must you be sure are part of the experiment?
a You must do the experiment several times (4 is a good number) in order to minimize random errors.
b. As you design your experiment, you need to consider possible sources of error (in advance), so that, if
possible, the experiment can be conducted to take them into account.
c. While running an experiment, you must be on the look out for errors.
d. Data must be carefully recorded and values calculated using the averages of the data for least error.
e. ALL OF THE ABOVE STATEMENTS ARE CORRECT.
8.) A pilot flying a Cessna airplane buzzes a neighbor's farm. While flying over her coffee mug falls out of the
plane, how far off the ground is the plane if her mug lands in the field in 8 seconds?
a) 156.8 meters
b) 78.4 meters
c) 313.6 meters
d) 39.2 meters
e) 627.2 meters
9.) Which of the following statements is TRUE.
a. While taking notes in room 46, a student experiences no forces outside his or her body.
b. In order to hold a pen, you must provide sufficient force upwards on the pen to counteract the force of
gravity pulling downwards on the pen.
c. Mass and weight are two words which describe the same concept.
d. Friction is the force that makes a rock drop to the earth when released from one's hand.
e. The wooden ball and the brass ball fell at different rates due to the different force of gravity each
experienced when our volunteer dropped them from above the table in a classroom demonstration.
10.) How much force is required to stop a falling 9.1 kg baby that hits the floor (on its bottom) at 0.7m/s if the
diaper allows for a 0.02 second stopping time?
a. 318.5 N up
c. 222.7 N down
e. 23 N up
b. 0.089 N down
d. 0.127 N up
11.) If you were measuring your response time with the meter stick in class and you caught the meter stick after
it dropped 0.15 m, what would your response time be?
a)
b)
c)
d)
e)
0.175 s
0.124 s
0.0055 s
0.03 s
5.37 s
12.) Possible sources of error in the mini-experiments on motion include which of the following? Look at
combinations of possibilities listed under a to e below statements A to E.
A. The student was walking along an incline.
B. Walker was already walking when the constant motion data was taken.
C. The measurement of a single concrete block might not be accurate for each successive block.
D. The timing of the motion could be off since the timer has a response time for starting and stopping the
watch.
E. While catching the falling meter stick, the person jumped the gun (started pinching meter stick a moment
before it was actually dropped.)
Choose:
a. A & B
b. D & E
c. B & C
d. A, B, & D
e. A, C, D, & E
13.) When moving a box of books (mass =m) into your apartment, a friend walks by and drops more books into
the box (new mass = 4m). If you continue to push with the same force F, what is your new acceleration after
the books are added?
a) same acceleration as before
b) new acceleration increases by a factor of 4
c) new acceleration is 16 times that of old
d) new acceleration is 1/4 of the old
e) new acceleration is 0
14.) Choose the graph which BEST describes the motion of the following example. A. A fox trots steadily
across the meadow B. It stops as it catches the delicate and delicious aroma of rabbit! C. When the rabbit stops
to eat some clover, the fox runs across the meadow picking up speed until it reaches the cowering rabbit where
(D.) it stops as the rabbit jumps down its hole
Distance
Velocity
(m)
(m/s)
A
B
Time
a)
D
(sec)
b)
Distance
(m/s)
(m)
B
Time
C
(sec)
B
A
Velocity
A
c)
C
D
C
A
d)
e) None of the above graphs describe the motion as stated in the question.
Time
(sec)
B
C
Time
(sec)
D
D