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.

3,423.

What is the gravitational potential due to a point mass m at a distance from it? (G = gravitational constant)

A.

-Gm2/r2

B.

-Gm2/r

C.

–Gm/Gr2

D.

–Gm/r

E.

–Gm/2

Correct answer is D

No explanation has been provided for this answer.

3,424.

Calculate the escape velocity of a satellite launched from the earth’s surface (Take g as 10ms-2 and the radius of the earth as 6.4 x 106m)

A.

8.00 x 106ms-1

B.

1.13 x104ms-1

C.

3.58x102ms-1

D.

5.59 x10-2ms-1

E.

3.95x10-2ms-1

Correct answer is B

V = 2gr

= 2 x 10 x 6.4 x 106

1.13 x 104ms-1

3,425.

A household refrigerator consumes electrical energy at the rate of 200 W. lf electricity costs 5 k per kWh, calculate the cost of operating the appliance for 30 days.

A.

N7.20

B.

N12.00

C.

N30.00

D.

N33.33

E.

N72.00

Correct answer is A

E = 200 x 30 x 24 Wh = 144000; Wh = 144KWh
Cost 144 x 5k = N7.20