Physics questions and answers

Physics Questions and Answers

If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.

3,411.

Which of the following is not a conductor of electricity?

A.

Human body

B.

Glass

C.

Silver

D.

Earth

E.

Copper

Correct answer is B

No explanation has been provided for this answer.

3,412.

Calculate the current, I in the diagram shown above.
(Neglect the internal resistance of the cell)

A.

4.0A

B.

2.0A

C.

1.0A

D.

0.5A

E.

0.1A

Correct answer is C

R = 2 + 2 = 4 Ω; 1/R = ¼ + ¼ = 2/4; R = 2Ω
∴ I = V/R = 2/2 = 1A

3,413.

Electrical resistance is the property of an electrical conductor that causes electrical energy to be converted into

A.

mechanical energy

B.

solar energy

C.

heat energy

D.

magnetic energy

E.

chemical energy

Correct answer is C

No explanation has been provided for this answer.

3,414.

In the diagram above, three identical lamps each of 100 W are connected in parallel across a potential difference of 250 V. Calculate the reading of the ammeter.

A.

7.5A

B.

2.5A

C.

1.2A

D.

0.8A

E.

O.4A

Correct answer is C

P = VI ; I = P/V = 100/250 = 0.4A each
Total current 3 x 0.4 = 1.2A

3,415.

The function of the magnanese (IV) oxide in a leclanche cell is to

A.

decrease the e.m.f. of the cell

B.

prevent local action in the cell

C.

prevent polarization in the cell

D.

increase the density of the electrolyte

E.

increase the resistance of the cell.

Correct answer is C

No explanation has been provided for this answer.