Physics Past Questions And Answers
Which of the following pairs of rays shows the widest separation in the spectrum of white light?
- A. green and blue
- B. orange and indigo
- C. blue and violet
- D. red and yellow
What is the best method of demagnetizing a steel bar magnet?
- A. Hammering
- B. Heating it
- C. Rough handling it
- D. Solenoid method
A man was moving round a circular path continuously for 4 minutes and covered the following distances in the times stated : Distance (in metres) 200, 400, 600, 300 Time(in minutes) : 1, 2, 3, 4 respectively. Which of the following statements is correct about the motion of the man?
- A. the man was moving without uniform velocity
- B. the speed was changing constantly
- C. the velocity was uniform
- D. it was an instance of motion in which both speed and velocity are the same
A machine whose efficiency is 60% has a velocity ratio of 5. If a force of 500N is applied to lift a load P, what is the magnitude of P?
- A. 1500N
- B. 500N
- C. 4166N
- D. 750N
A liquid of volume 2.00 m3 and density 1.00 x 103 is mixed with 3.00 m3 of another liquid of density 8.00 x 103kg m-3. Calculate the density of the mixture [Assuming there is no chemical reaction]
- A. 5.20 x 102 kg m-3
- B. 1.13 x 103 kg m-3
- C. 8.80 x 102 kg m-3
- D. 5.20 x 102 kg m-3
The reason for laminating the soft iron core of a transformer is to?
- A. reduce eddy current.
- B. reduce magnetic flux.
- C. increase the magnetic flux.
- D. reduce its efficiency.
The primary coil of a transformer has N turns and is connected to a 120 V a.c. power line. If the secondary coils has 1 000 turns and a terminal voltage of 1 200 volts, what is the value of N?
- A. 120
- B. 100
- C. 1 000
- D. 1 200
A body moves along a circular path with uniform angular speed of 0.6 rads-1 and at a constant speed of 3.0ms-1. Calculate the acceleration of the body towards the centre of the circle.
- A. 25.0ms-2
- B. 5.4 ms-2
- C. 5.0ms-2
- D. 1.8 ms-2
Which of the following statements about sound wave is not correct? Sound waves can be
- A. reflected
- B. refracted
- C. diffracted
- D. polarized
The phenomenon that shows that increase in pressure lowers the melting point can be observed in
- A) sublimation
- B) condensation
- C) coagulation
- D) regelation