Waec Physics 1998 Past Questions and Answers

Question 36:

• WAEC 1998

Calculate he wavelength of a note which is one octave lower than a note of 256Hz in a medium in which the speed of sound is 352ms^-1

A. 0.69m
B. 1.38m
C. 2.75m
D. 5.50m
E. 9.30m

Question 37:

• WAEC 1998

Which of the following are both mechanical and transverse?

A. Infra-red rays
B. Gamma rays
C. Sound waves
D. Water waves
E. Micro waves

Question 38:

• WAEC 1998

An electromagnetic wave of frequency 5.0 x 10¹⁴Hz, is incident on the surface of water of refractive index \(\frac{4}{3}\). Taking the speed of the wave in air as 3.0 x 10⁸ms^-1, calculate the wavelength of the wave in water.

A. 2.2 x 10^-6m
B. 1.7 x 10^-7m
C. 8.0 x 10^-7m
D. 6.0 x 10^-7m
E. 4.5 x 10^-7m

Question 39:

• WAEC 1998

The gravitational force of the moon is one-sixth that of the earth. If a body weighs 6.0N on the moon. Calculate its weight on the earth

A. 36.0N
B. 12.0N
C. 6.0N
D. 2.0N
E. 1.0N

Question 40:

• WAEC 1998

In the electrical method of magnetisation, the polarity of the magnet depends on the

A. Amount of current passed
B. Direction of current
C. Magnetic material used
D. Size of the magnetic material
E. Orientation of the magnetic material in space