Jamb Physics 2004 Past Questions and Answers

Question 1:

• JAMB 2004

A generator manufacturing company was contracted to produce an a.c dynamo but inadvertently produced a d.c dynamo. To correct this error, the

A. Armature coil should be made of silver
B. Commutator should be replaced with slip ring
C. Commutator should be replaced with split rings
D. Armature coil should be made of aluminium

Question 2:

• JAMB 2004

A generator manufacturing company was contracted to produce an a.c dynamo but inadvertently produced a d.c dynamo. To correct this error, the

A. Armature coil should be made of silver
B. Commutator should be replaced with slip ring
C. Commutator should be replaced with split rings
D. Armature coil should be made of aluminium

Question 3:

• JAMB 2004

A radioisotope has a decay constant of 10\(^{-7}\)s\(^{-1}\). The average life of the radioisotope is

A. 1.00 x 10⁷s
B. 6.93 x 10⁶s
C. 1.00 x 10^-7s
D. 6.93 x 10⁷s

Question 4:

• JAMB 2004

An a.c circuit of e.m.f 12V has a resistor of resistance 8Ω connected in series to an inductor of inductive reactance 16Ω and a capacitor capacitive reactance 10Ω. The current flow in the circuit is

A. 1.4A
B. 1.2A
C. 12.0A
D. 14.0A

Question 5:

• JAMB 2004

For semi conductor to have negative temperature coefficient of resistance implies that

A. Their resistance decrease with temperature
B. The resistance increase with temperature
C. Their resistance is constantly changing with temperature
D. They have electrons and holes at high temperature