2003 - WAEC Physics Past Questions and Answers - page 4
31
Two identical cells each of e.m.f 2v and internal resistance 1.0\(\Omega\) are connected in parallel. The combination is connected to an external load of 1.5\(\Omega\). Calculate the current in the circuit
A
0.57A
B
1.00A
C
1.14A
D
2.00A
32
Which of the following factors does not affect the the electric resistance of a wire?
A
length
B
mass
C
temperature
D
cross sectional area
correct option: b
Users' Answers & Comments33
A current of 10A passes through a conductor for 10s, calculate the charge flowing through the conductor
A
100.0C
B
10.0C
C
1.0C
D
0.1C
34
A lamp is rated 240V 60W, calculate the resistance of its filament
A
240\(\Omega\)
B
360\(\Omega\)
C
960\(\Omega\)
D
1440\(\Omega\)
35
The maximum power dissipated by a 100\(\Omega\) resistor in a circuit is 4W. Calculate the voltage across the resistor
A
10V
B
20V
C
25V
D
400V
36
One difference between a reactance and a resistance in an alternating current circuit is
A
resistance is larger than reactance
B
energy is not diaaipated in a reactance
C
energy is stored in a resistance but not in a reactance
D
the current in a reactance is lower than in the resistance
correct option: d
Users' Answers & Comments37
The direction of induced current in a straight wire placed in magnetic field is determined by using
A
Fleming's right hand rule
B
Maxwell's screw rule
C
Faraday's law
D
Lenz's law
correct option: a
Users' Answers & Comments38
Which of the following statements about an electromagnet is correct?
A
it is a temporary magnet
B
its strength depends on the current
C
its stength depends on the number of turns in its coil
D
it has permanent poles
correct option: d
Users' Answers & Comments39
Which of the following statements is not true of the isotopes of an element? They
A
are atoms of the same element
B
have the same chemical properties
C
have the same atomic number
D
have the same mass number
correct option: d
Users' Answers & Comments40
Which of the following statements is true of ultra violet radiations? It
A
supports the sensation of hearing
B
does not cause the emission of electrons from metals
C
is an electromagnetic wave
D
is not capable of causing sun burns
correct option: c
Users' Answers & Comments