Jamb Physics 1995 Past Questions and Answers

Question 36:

• JAMB 1995

If the maximum voltage across a 100ohms resistor is 20V, then the maximum power it can dissipate is

A. 5.00W
B. 4.00W
C. 2.00W
D. 25W

Question 37:

• JAMB 1995

Which of the following is required to convert a milliammeter to an ammeter?

A. A high resistance in parallel
B. A high resistance in series
C. A low resistance in parallel
D. A low resistance in series

Question 38:

• JAMB 1995

The primary winding of a transformer has 400 turns and its secondary has 100 turns. If a source of e.m.f. of 12V is applied to the primary, the secondary e.m.f. will be

A. 3V
B. 6V
C. 24V
D. 48V

Question 39:

• JAMB 1995

A light of energy 5eV falls on a metal and the electrons with a maximum kinetic energy of 2eV are ejected. The work function of the metal is

A. 0.4eV
B. 2.5eV
C. 3.0eV
D. 7.0eV

Question 40:

• JAMB 1995

The half-life of a radio-active element is 9 days, what fraction of atoms has decayed in 36 days?

A. \( \frac{1}{16} \)
B. \( \frac{1}{4} \)
C. \( \frac{1}{2} \)
D. \( \frac{15}{16} \)