Physics Past Questions and Answers

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:

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:

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:

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:

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