Question 1
The diagram below shows a portion of a micrometer screw gauge used to measure the diameter of a metal pipe. The reading on the gauge when the jaws were fully closed without the pipe was 0.012cm.
What is the diameter of the pipe
Answer
5.50 + 12 = 5.62M
5.62 - 0.12 = 5.50mm
5.62 - 0.12 = 5.50mm
Question 2
The figure below shows a ray of light incident on a plane mirror.
a) What is the angle of reflection
b) The mirror is rotated clockwise through an angle of 10o.Through what angle does the reflected ray make with the horizontal
Answer
a) Angle i = angle r
900-800 = 100
R = 100
b) Angle rotated = 2 x 10 = 200
Angle made between the reflected ray and horizontal
90 - 20 = 700
900-800 = 100
R = 100
b) Angle rotated = 2 x 10 = 200
Angle made between the reflected ray and horizontal
90 - 20 = 700
Question 3
A device allows current of 10A to pass through a point in a circuit for 25 seconds. Calculate the total charge passing through the point within the period
Answer
Q = It
= 10 × 25 = 250 coulombs
= 10 × 25 = 250 coulombs
Question 4
Why is attraction not a sure test when establishing the polarity of a magnet
Answer
Attraction is not sure test because it can occur between unlike poles of magnets or between a magnet and unmagnified magnetic material while repulsion can only occur between like poles of magnets.
Question 5
The figure below shows a light body floating in a container
State and explain the observation when a stream of air is blown over the mouth of the container at high speed as shown
Answer
The light body moves to the mouth of the container. When the air is blown, the velocity of the air increases, reducing the pressure at the top reduces. In turns the pressure inside the container reduced making the ball to rise.