Jamb Physics 1979 Past Questions and Answers

Question 41:

• JAMB 1979

In a given circuit, the cell P has an emf 1.5V and an unknown internal resistance while cell Q has an emf 2.0V and an internal resistance of 1 ohm if the ammeter reads 50m A, Then r is equal to

A. 0.5 ohm
B. 0.62 ohm
C. 1.0 ohm
D. 2.0 ohm
E. 3.0 ohm

Question 42:

• JAMB 1979

An air column 10cm in length is trapped into the sea end of a capillary tube by a 15cm column of mercury with the tube held vertically as shown above. On inverting the tube the air column becomes 15cm long. The atmospheric pressure during the experiment is

A. 90cm
B. 76cm
C. 75cm
D. 60cm
E. 50cm

Question 43:

• JAMB 1979

In a resonance tube experiment, which is illustrated above, the velocity of sound in air is 327.68m/s, the frequency of the turning fork used is therefore

A. 128HZ
B. 256HZ
C. 512HZ
D. 768HZ
E. 1024HZ

Question 44:

• JAMB 1979

A uniform bean HK of length 10m and weighing 200N is supported at both ends as shown above. A man weighing 1000N stands at a point P on the beam. If the reactions at point H an K respectively are 800N and 400N, Then the distance HP is

A. 4m
B. 3.5m
C. 3m
D. \( 6 \frac{2}{3} \)m
E. 7m

Question 45:

• JAMB 1979

Fig 8 shows a current I flowing in a copper wire situated in a magnetic field existing between the pole-pieces of a horse-shoe magnet.
Which of the following statements is correct?

A. The wire will experience a force in the direction into the paper
B. The wire will experience a force in the direction out of the paper
C. The wire will vibrate in a direction into and out of the paper
D. The wire will move in the direction of the field i.e toward the s-pole
E. The wire will not move because it is made of copper which is non magnetic