5:00 – 7:00 p.m.
Student’s Name: ………………..………………….…………………………………….…………
Student’s Number: ….…………………………………… Section: ……………………
Choose your Instructor’s Name:
Prof. Fikry El-Akkad
Prof. Yacoub Makdisi
Dr. Hasan Raafat
Dr. Ahmed Al-Jassar
Dr. Fatema Al Dosari
Grades:
Dr. Abdel Khaleq
Dr. Abdul Mohsen
Dr. Tareq Al Refai
Dr. Belal Salameh
Dr. Nasser Demir
# Q1 Q2 Q3 Q4 Q5 SP1 SP2 SP3 SP4 SP5 SP6 SP7 SP8 SP9 SP10 LP1 LP2 LP3 Total
Pts
1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 5 5 5 40
:
1.
Answer all questions and problems.
2.
Full mark = 40 points as arranged in the above table. i.
5 Q uestions ii.
10 S hort P roblems iii.
3 L ong P roblems.
3.
No solution = no points.
4.
Use SI units.
5.
Check the correct answer for each question.
6.
Assume g = 10 m/s 2 .
7.
Mobiles are strictly prohibited during the exam.
8.
Programmable calculators, which can store equations, are not allowed.
9.
Please write down your final answer in the box shown in each problem .
10.
Cheating incidents will be processed according to the university rules.

Kuwait University – Science College – Physics dept. – PHYS 101                                                                               Fall 2015/2016 (December, 2015)
Part I: Questions (Choose the correct answer, one point each)
Q1. A particle moves with constant acceleration in the positive x-direction with increasing velocity .
Which one of the following must be correct?
* ∙ 0 & are in the same direction.
*
* ∙
* ∙
θ = 0 cos θ =1
∙
*
Q2. A small car moves with constant speed on a smooth track as shown in the figure. The normal force on the car at the points A, B, and C are N
A
, N
B
and N
C
respectively. Which of the following is correct?
* N
A
= N
B
= N
C
N
A
= mg
* N
A
> N
B
> N
C
N
B
= mg – mv 2 /R
* N
C
> N
A
> N
B
N
C
= mg + mv 2 /R
B
R R
* N
B
> N
C
> N
A
A C
* N
C
> N
B
> N
A
Q3. The blocks A and B move from rest on a smooth surface under the effect of the same force F . They cover the same distance d .
If m
A
= 2m
B their kinetic energies at this end
point are related as
* K 2K
* K K
* K K
* 4k
* K K
W =
Fd
Fd
K
K
K
&
K
0
F
F
Q4. Two objects A and B, have the same momentum P. If
*
* /2
A
B
, then d
*
*
* yields higher K
Q5. Two points are painted on a rotating disk of radius R. Point A is at distance R and point B is at distance R/2 from the rotation axis, as shown in the figure. The angular speeds & of points
A & B respectively are related by :
*
*
*
2 Rotating objects means
Same Δ θ
Same
*
*
√2
0
Same α
R B
A
1

Kuwait University – Science College – Physics dept. – PHYS 101                                                                               Fall 2015/2016 (December, 2015)
Part II: Short Problems (2 point each) show your solutions in details
SP1.
In the figure shown, find the net force on block B (Neglect friction)
Σ ⟹ 4 /
A
2 kg
B
5 kg
Σ
C
8 kg
5 4 20
SP2.
A particle is projected from the ground level with initial velocity
Answer:
30 50
20
/ .
F = 60
Find the horizontal distance (range in m) on the ground level .
or
300
1 0 0 50
10
10
R
∆
1
30 10
300
Answer: 300
SP3.
A ball of mass 0.12 kg is dropped from a height 45 m to the ground. It rebounds to a height 20 m.
Find the average force (in N) exerted on the ball from the ground if the contact time is
. Neglect air resistance.
45 m
20 m
2 2 10 45 30 / ground
2
.
500
2 10 20 20 /
Answer: 500
2

Kuwait University – Science College – Physics dept. – PHYS 101                                                                               Fall 2015/2016 (December, 2015)
SP4.
A car starts from rest from point (a) and moves toward point (c) with constant acceleration . The velocities at points (b) and (c) are 12m/s and 18m/s respectively. They are 200 m apart. Find the average velocity (in m/s) of the car from point (a) to point (c) .
9 /
(a) v = 0
(b) v = 12 m/s
200 m
(c) v = 18 m/s
Answer: 9 /
SP5.
A uniform square sheet of side 24 cm is divided to four similar squares as shown in the figure. The square D is removed from this combination. Find the center of mass (in cm) of the remaining three squares, A, B and C with respect to the origin of the main square O.
(in unit vector notation) y
12 12
A D
2 2 or 0 6 6 3
2 2
B
O
C
Answer: 2 2
SP6.
A 2 kg carte is pulled up a 36.9 ̊ rough incline with an initial speed of 6m/s. If the pulling force is
90 N parallel to the incline and the coefficient of kinetic friction is 0.325, what is the final speed of the carte after it is pulled 5.0 m up the incline ? x
Σ Δ
36.9 ̊
F
90 5
2 sin
2 10 0.6 5
2 6 cos
0.325 2 10 0.8 5 n
F
OR
Σ
√450 60 26 36 20 /
⟹ 36.4 /
2 ∆ ⟹ 20 / mg sin θ
μ mg cos θ
Answer: 20 /
3

Kuwait University – Science College – Physics dept. – PHYS 101                                                                               Fall 2015/2016 (December, 2015)
SP7.
A car of mass 2000 kg negotiates without slipping a banked curved road of radius 40 m with speed of 12 m/s. Find the banked angle to accomplish this. (Neglect friction)
N cos θ sin cos
N sin θ mg tan ⟹ 0.36
20°
Answer: 20°
SP8.
A wheel rotates 3.19 revolutions in 2.0 s as it is uniformly brought to rest. Calculate the initial angular velocity (in rad/s) of the wheel .
0, 2 , 3.19 , ?
3.19 2 20 or
1 0 2
20 0
20 /
2 20 2
1
20 2
20 /
4
Answer: 20 /
SP9.
A particle of mass 2kg is acted on by two forces and . Accordingly the particle moves due east with acceleration of 4m/s 2 . If is 12N due north, find (in N) in unit
vector notation.
2 4 8 or y
(north)
F
1
12 12 ̂
2
2 4 m a x
(east)
8 ̂ 12 ̂ 8 ̂ 12 ̂
Answer: 8 12
4

Kuwait University – Science College – Physics dept. – PHYS 101                                                                               Fall 2015/2016 (December, 2015)
SP10.
A shell of mass 60 kg is fired from the ground level with velocity 40 50 / . At the maximum height it explodes into three parts, two of them have equal masses of 15kg each with equal and opposite velocities of 20 m/s (up and down) as shown in the figure. The third part m
3
has mass of 30 kg starts to move with v
3
due east. Find the velocity (in m/s) of the center of mass of the three fragments just after the explosion. (Neglect air resistance and all other external forces)
is constant v
1
(east) v
3 v
2
40 ̂ / ground
Answer: 40 ̂ /
Part III: Long Problems (5 points each) show your solutions in details
LP1.
A uniform rod of mass m = 2kg and length of l
= 1.2m is pivoted from its end (o) and is kept in horizontal position. It is then released from rest (I cm
= 1
12 ml
2 ). Find a.
The moment of inertia I o
(in kg m 2 ) about the pivot point (o). b.
The initial tangential acceleration (in m/s 2 ) at the far end (a). c.
The linear speed (in m/s) of the far end (a) as it passes the vertical position.
(Hint: Solve the problem by symbols ( m, l, g
) then substitute the values in the last steps.) a.
(o) l
(a) b.
15 / c.
l
(a)
3 6 /
Answer:
Answer: 15 /
Answer: 6 /
5

Kuwait University – Science College – Physics dept. – PHYS 101                                                                               Fall 2015/2016 (December, 2015)
LP2.
A uniform disk, of mass M = 4 kg and radius R = 30 cm is mounted on a fixed horizontal axle.
A block of mass m = 2 kg hangs from a massless cord that is wrapped around the rim of the disk.
The system starts from rest. Find a.
The acceleration (in m/s 2 ) of the falling block b.
The tension (in N) in the cord. c.
The total kinetic energy (in J) of the system after 0.6 s. d.
The length (in m) of the unwrapped cord during this 0.6 s.
I cm
= ½ MR 2 The cord does not slip, and there is no friction at the axle.
M m
R
(Hint: Solve the problem by symbols ( m, M, R, g ) then substitute the values in the last steps.) a.
5 / b.
c.
4 5 10
0 5 0.6
3 /
2 d.
Δ
4
0 5 0.6
0.9
3 18
Answer: 5 /
Answer: 10
Answer: 18
Answer: 0.9
6

Kuwait University – Science College – Physics dept. – PHYS 101                                                                               Fall 2015/2016 (December, 2015)
LP3.
A and B are two blocks of equal masses of 2 kg each.
An ideal spring of k = 900 N/m is attached to block A which is moving with a speed of 2m/s to the left. Block B is released from a height of
5 m and slides along a smooth surface and then strikes block A on the horizontal track. The two blocks have a head on elastic collision .
(Hint: at maximum compression the two blocks are very close and move momentarily with the same speed, v)
Find a) The speed v (in m/s) of the combined masses at the maximum compression of the spring. b) The maximum compression (in m) of the spring. c) The velocities (in m/s) of each block after block B has lost contact with the spring. a.
Before
B
2
10 2 2
4 /
10 /
5 m v
Ai
= 2m/s
A b.
10 2
0.4 c.
10 2
10 2
2 /
10 /
2 4 900
Or c. Apply the concepts of interchanging velocities
10 /
2 /
Eq.1
Eq.2
B
Answer:
Answer:
Answer:
A
After
4 /
0.4
2 /
10 /
7