2006 - JAMB Physics Past Questions and Answers - page 3
21
If the radius of the earth is 6.4 x 106m, the escape velocity of a satellite from the earth is?
[g = 10 ms-2]
[g = 10 ms-2]
A
1.13 x 104 ms-1
B
9.00 x 103 ms-1
C
8.00 x 103 ms-1
D
1.27 x 104 ms-1
22
The component of vector X along the direction of vector Y is zero when
A
X and Y are in opposite directions to each other
B
X is at an angle of 45° to Y
C
X is perpendicular to Y
D
X and Y are parallel to each other
correct option: d
Users' Answers & Comments23
The correct unit of energy density is?
A
kg m3 s-2
B
kg m2 s-2
C
kg m-3 s-2
D
kg m-1 s-2
correct option: d
Users' Answers & Comments24
I. Work done by load is always less than the work done by effort.
II. All machines are made of levers, pulleys, screws and gear wheels.
III. A fishing rod is a machine.
Iv. Effort is always larger than load.
which of statements above about machines are true?
II. All machines are made of levers, pulleys, screws and gear wheels.
III. A fishing rod is a machine.
Iv. Effort is always larger than load.
which of statements above about machines are true?
A
I and III
B
III and IV
C
I and III
D
II and III
correct option: c
Users' Answers & Comments25
The energy associated with the emitted photon when a mercury atom changes from one state to another is 3.3 ev. calculate the frequency of the photon.
[e = 1.6 x 10-19c; h = 6.6 x 10-13js]
[e = 1.6 x 10-19c; h = 6.6 x 10-13js]
A
1.3 x 10-15 Hz
B
3.1 x 1052 Hz
C
3.2 x 10-53 Hz
D
8.0 x 1014 Hz
correct option: d
E = hf
f = (E)/h
∴ f = (3.3 x 1.6 x 10-19)/6.6 x 10-34
= 0.8 x 1015 = 8.0 x 1014 Hz
Users' Answers & Commentsf = (E)/h
∴ f = (3.3 x 1.6 x 10-19)/6.6 x 10-34
= 0.8 x 1015 = 8.0 x 1014 Hz
26
The process through which free electrons leave the surface of hot metal is known as?
A
photon emission
B
photo emission
C
thermionic emission
D
electron emission
correct option: c
Users' Answers & Comments27
The battery connection that permits current to flow across a p-n junction is called?
A
reverse baised
B
forward baised
C
amplification.
D
rectification
correct option: b
Users' Answers & Comments28
One of the properties of gamma rays is that they are?
A
neutral
B
massive
C
positively charged
D
negatively charged
correct option: a
Users' Answers & Comments29
A radioactive element has a half life of 4 days. The fraction that has decayed in 16 days is?
A
(15)/16
B
(1)/16
C
(3)/4
D
(1)/4
correct option: a
16 days = 4 half lives.
The fraction left 16 days = after 4 half live, = (1/2)4 = (1)/16.
∴ fraction delayed = (15)/16
Users' Answers & CommentsThe fraction left 16 days = after 4 half live, = (1/2)4 = (1)/16.
∴ fraction delayed = (15)/16
30
The theory of electronic conduction in solids, which satisfactorily explains the properties of conductors, insulators and semi-conductor,is?
A
string theory
B
particle theory
C
group theory
D
band theory
correct option: d
Users' Answers & Comments