Jamb Physics 1999 Past Questions and Answers

Question 26:

• JAMB 1999

Four cells each of e.m.f 1.5V and internal resistance of 4Ω are connected in parallel. What is the effective e.m.f. and internal resistance of the combination?

A. 6.0V, 16Ω
B. 6.0V, 1Ω
C. 1.5V, 4Ω
D. 1.5V, 1Ω

Question 27:

• JAMB 1999

A 3000W electric cooker is to be used on a 200V mains circuit. Which of the fuses below can be used safely with the cooker?

A. 2A
B. 5A
C. 10A
D. 20A

Question 28:

• JAMB 1999

A galvanometer has a resistance of 5Ω. By using a shunt wire of resistance 0.05Ω, the galvanometer could be converted to an ammeter capable of reading 2Amp. What is the current through the galvanometer?

A. 2mA
B. 10mA
C. 20mA
D. 25mA

Question 29:

• JAMB 1999

In fleming's right-hand rule, the thumb, the forefinger and the middle finger if held mutually at right angles represent respectively, the

A. Motion, the field and the induced current
B. Induced current, the motion and the field
C. Field, the induced current and the motion
D. Induced current, the field and the motion

Question 30:

• JAMB 1999

At what frequency would a 10H inductor have a reactance of 2000Ω?

A. π/200Hz
B. π/100Hz
C. 100/Ï€Hz
D. 100Ï€Hz