2012 - JAMB Physics Past Questions & Answers - page 1

1
In order to remove the error of parallax when talking measurements with a metre rule, the eye should be focused
A
slantingly towards the right on the markings
B
slantingly towards the left on the markings
C
vertically downwards on the markings
D
vertically upwards on the markings
CORRECT OPTION: c
2
A load is pulled at a uniform speed along a horizontal floor by a rope at 45o to floor. If the force in the rope is 1500N, what is the frictional force on the load ?
A
1524N
B
1350N
C
1260N
D
1061N
CORRECT OPTION: d
F = mg cos 45o = 1500 x 0.708
3
Calculate the total distance covered by a train before coming to rest if its initial speed is 30ms-1 with a constant retardation of 0.1m-2
A
5500m
B
4500m
C
4200m
D
3000m
CORRECT OPTION: b
S = \(\frac{V^2 - U^2}{20}\)

S = \(\frac{0^2 - 30^2}{2 \times 0.1}\)
4
A car starts from rest and moves with a uniform acceleration of 30ms-2 for 20s. Calculate the distance covered at the end of the motion
A
6km
B
12km
C
18km
D
24km
CORRECT OPTION: a
S = \(ut + \frac{1}{2}at^2\)

S = \(0 \times 2 + \frac{1}{2} \times 30 \times 20^2\)
5
A rocket is fired from the earth's surface to a distant planet. By Newton's law of universal gravitation, the force F will
A
increase as r reduces
B
increase as G varies
C
remains constant
D
increases as r increases
CORRECT OPTION: a
6
If a freely suspended object is pulled to one side and released, it oscillates about the point of suspension because the
A
acceleration is directly proportional to the displacement
B
motion is directed away from the equilibrium point
C
acceleration is directly proportional to the square of the displacement
D
velocity is minimum at the equilibrium ponit
CORRECT OPTION: a
7
An object moves in a circular path of radius 0.5m with a speed of 1ms-1 What is its angular velocity?
A
8 rads-1
B
4 rads-1
C
2 rads-1
D
1 rads-1
CORRECT OPTION: c
W = \(\frac{v}{r} = \frac{1}{0.5}\)
8
An object of mass 20kg slides down an inclined plane at an angle of 30o to the horizontal. The coefficient of static friction is?
[g = 10ms-2]
A
0.2
B
0.3
C
0.5
D
0.6
CORRECT OPTION: d
\(\mu = tan\theta = tan30\)
9
A block and tackle is used to raise a load of 250N through a vertical distance of 30m. What is the efficiency of the system if the work done against friction is 1500J?
A
62.5%
B
73.3%
C
83.3%
D
94.3%
CORRECT OPTION: c
Y = \(\frac{work output}{work input} \times \frac{150}{1}\)

Y = \(\frac{250 \times 30}{250 \times 30 + 1500} \times \frac{150}{1}\)
10
If a load of 1 kg stretches a cord by 1.2cm, what is the force constant of the cord? {g=10ms-2}
A
866Nm-1
B
833Nm-1
C
769Nm-1
D
667Nm-1
CORRECT OPTION: b
K = \(\frac{F}{e}\)

K = \(\frac{1 \times 10}{\frac{0.2}{100}}\)

K = \(\frac{10}{12} \times \frac{1000}{1}\)
Pages: