Jamb Physics 1982 Past Questions and Answers

Question 16:

• JAMB 1982

The combination of sound waves with different frequencies is known as

A. Interference
B. Diffraction
C. Superposition
D. Forced vibration
E. Resonance

Question 17:

• JAMB 1982

Why does a piece of cork float on water?

A. There is no upthrust on it when completely immersed in water
B. The upthrust on it when completely immersed in water is greater than its weight in air
C. The upthrust on it when completely immersed in water is less than its weight in air
D. Its specific gravity is greater than that of water
E. Its specific gravity is the same as that of water

Question 18:

• JAMB 1982

A rod of length 10cm is heated through 100^oC and its final length is 10.26cm. What is the co-efficient of linear expansion of the rod?

A. 0.026 per degree centigrade
B. 0.00026 per degree centigrade
C. 0.26 per degree centigrade
D. 1.0026 per degree centigrade
E. 0.0026 per degree centigrade

Question 19:

• JAMB 1982

If the refractive index of a medium is V2, what is the critical angle?

A. 45^o
B. 50^o12'
C. 56^o25'
D. 75^o
E. 90^o

Question 20:

• JAMB 1982

In copper plating, a current of 0.5A is allowed for cathode area of 100cm². If this current is maintained constant for 100 minutes, the thickness of the copper deposited will be approximately (the electrochemical equivalent of copper = 0.0003g/^oC, density of copper = 10^-4g/cm³ )

A. 10^-2mm
B. 10^-3mm
C. 10^-4mm
D. 10^-5mm
E. 10^-6mm