JAMB Physics Past Questions & Answers - Page 17

81.

The graph of pressure (P) against the reciprocal of the volume (I/V) in Boyles's law is a?

A.

hyperbola

B.

parabola

C.

curve

D.

straight line

Correct answer is D

The graph of pressure (P) against the reciprocal of the volume (I/V) is a straight line passing through the origin.

82.

Which expression gives magnetic flux?

A.

qVB sin\(\theta\)

B.

\(\frac{\mu \phi I}{2 \pi r}\)

C.

BA cos \(\theta\)

D.

-N \(\frac{d \phi}{dt}\)

Correct answer is C

the magnetic flux through a surface is the surface integral of the normal component of the magnetic field B over that surface.

It is usually denoted Φ or ΦB. The SI unit of magnetic flux is the weber

Mathematically it is represented as B = Φ/A

 where B is magnetic flux density in teslas (T),

Φ is magnetic flux in webers (Wb), and

A is area in square meters (m2).

83.

The amount of energy required to change a kilogram of ice block into water without a change in temperature is?

A.

specific latent heat of fusion of ice

B.

specific heat capacity of ice

C.

heat capacity of ice

D.

specific heat of vaporization of ice

Correct answer is A

Specific latent heat of fusion of a substance is the quantity of heat required to convert the unit mass of the substance from the solid to the liquid state without change in temperature.

84.

The gravitational pull on the moon is \(\frac{1}{6}\) that of the earth. If a body weighs 6.0 N on the moon, what will be the weight on the earth?

A.

6.0 N

B.

5.0 N

C.

12.0 N

D.

36.0 N

Correct answer is D

A person would weigh six times less on the moon than they do on Earth.

OR

A person would weigh six times more on the earth than they do on moon.

 

\(\frac{1}{6} of x\) = 6.0N on the moon

x = 6 * 6 = 36 

 

85.

The eclipse of the moon occurs when?

A.

the moon reflects the rays from the sun to the earth

B.

the moon comes exactly between the earth and the sun

C.

the earth comes exactly between the moon and the sun

D.

the sun comes exactly between the earth and the moon

Correct answer is C

Eclipse of the moon occurs when the earth comes between the sun and the moon.