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Physics 111 N Final Exam

Please answer all problems on the blank
paper provided.
Clearly print your name and student ID on
every sheet you use.
Please hand in your formula sheet along
with your answers

Course ID : 10076

Prof. Jozef Dudek

Unless instructed otherwise, you must
show working, or explain how you came
to your answer for all questions.
You cannot get full credit on a question
unless working is shown. Partial credit
will be awarded for working which is partially correct.
Drawing appropriate labeled diagrams
may be of help.

There are nine(9) questions
plus two(2) bonus questions for extra credit.
You have 3 hours to complete as much of the test as you can.

3
3
The density of water is approximately 1.00 × 10 kg/m

Take the universal gravitational constant to have the following value: G = 6.67 × 10−11 Nm2 kg−2

Take the magnitude of acceleration due to gravity at the surface of the Earth to have the following value: g = 9.80 ms−2

Physics 111N

FINAL EXAM

Physics 111 N Final Exam

Course ID : 10076

Prof. Jozef Dudek

Question 1.
[1.1] Two cars travel on the parallel lanes of a two-lane road. The cars’ motions are represented by

the position versus time graph shown in the figure.
1. at what time do the cars pass one another? At this time are they traveling in the same direction? 2. at what time (if any) does car #1 momentarily stop? At what time (if any) does car #2 momentarily stop?

3. where is car #1 when car #2 changes direction?
4. what is the average velocity of car #1 in km/hr?
5. estimate the instantaneous velocity (in km/hr) of car #2 at t = 43 min ?

x / km
car #1

20

10
car #2
0

20

10

30

40

t / min

[1.2] Here is a plot of velocity versus time for an object that travels along a straight line (positive

direction to the right) with a varying velocity.

v/ m/s

1. at what time(s) is the object at rest?

20

2. what is the average acceleration for the first 20 secs?
3. during which periods of time is the object moving to
the left?

10

4. what is the velocity at t = 30 s?
0
-10

Physics 111N

10

20

30

40

t /s
[15 points]
FINAL EXAM

Physics 111 N Final Exam

Course ID : 10076

Prof. Jozef Dudek

Question 2.
[2.1] A ball is tossed vertically into the air, when it reaches the highest point in its trajectory it has (a) velocity pointing upward and zero acceleration
(b) zero velocity and zero acceleration
(c) zero velocity and acceleration pointing downward
(d) velocity pointing downward and acceleration pointing downward [2.2] At one instant in time an object has the velocity and acceleration vectors shown, which of the following is true for the object a very short time later:

a
v

(a) the object has slowed down
(b) the object has sped up
(c) the object is moving in a di!erent direction at the same speed (d) it is not possible for acceleration to be perpendicular to velocity

[2.3] The pilot of an Eksian bomber plane flying horizontally at 20 m/s releases a 10 kg bomb hoping for it to land on the Wiyan trench.
Eksian
1. Sketch the trajectory of the bomb.
bomber
2. How many seconds after release does
20 m/s
the bomb hit the trench (100 m below
the plane) ?
3. What is the horizontal distance from the
bomber (when the bomb is released) to
100 m
the Wiyan trench?
4. What is the speed of the bomb when it
reaches the trench? What would the
speed be if the bomb was of mass 20 kg?
5. The Eksian trench is 130 m horizontally
from the position of the bomber when
the bomb is released. At what speed
would the bomber have to be traveling
for the 10 kg bomb to hit the Eksian trench?

Wiyan
trench

Eksian
trench

[20 points]
Physics 111N

FINAL EXAM

Physics 111 N Final Exam

Course ID : 10076

Prof. Jozef Dudek

Question 3.
[3.1] A greased block of mass 20 kg is pulled along a smooth horizontal surface by a string as shown below. The grease...
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