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.

2,591.

The specific latent heat of fusion of lead is the amount of heat required to

A.

melt lead at its melting point

B.

heat a unit mass of lead through 1oC

C.

change the state of a unit mass of lead at its melting point

D.

change the state of a unit mass of lead at its boiling point

Correct answer is C

No explanation has been provided for this answer.

2,592.

The mode of heat transfer which does not require a material medium is

A.

conduction

B.

radiation

C.

convection

D.

propagation

Correct answer is B

No explanation has been provided for this answer.

2,594.

A rectangular tank contains water to a depth of 2m, if the base is 4m x 3m, calculate the force on the base (Density of water = 103kgm-3, g = 10ms-2)

A.

1.4 x 102N

B.

24 x 104N

C.

2.0 x 104N

D.

1.7 x 103N

Correct answer is B

Volume = 2 x 4 x 3 = 24m3

mass = V x D = 24 x 103

F = mg

= 24 x 103 x 10

= 24 x 104

2,595.

A constant force of magnitude F acts on an object of mass 0.04kg initially at rest at a point O. if the speed of the object when it has moved 50m from O is 500ms-1, what is the value of F?

A.

0.4N

B.

100.0N

C.

250.0N

D.

1000.0N

Correct answer is B

F = ma and V2 = U2 + 2aX

F = m\(\frac{(V^2 - U^2)}{2X}\)

= 0.04\(\frac{(500^2 - 0^2)}{2 \times 50}\)

F = 100N