Waec Physics 2009 Past Questions and Answers

Question 31:

• WAEC 2009

Which of the following is not a part of the electro-magnetic spectrum?

A. X-rays
B. Microwaves
C. Infrared radiation
D. Alpha rays

Question 32:

• WAEC 2009

Sound interference is necessary to produce the phenomenon of

A. Beats
B. Doppler effect
C. Acoustic resonance
D. Echo

Question 33:

• WAEC 2009

A satellite in circular motion around the earth does not have

A. A gravitational force acting on it
B. A uniform velocity
C. An acceleration
D. A centripetal force acting on it

Question 34:

• WAEC 2009

When a conductor mounted on an insulating stand is charged and left for sometime, the conductor eventually loses all its charges. This is because the

A. Electric charges evaporate from the surface of the conductor
B. Charges are connected to earth
C. Charges on the conductor are neutralized by opposite charges from the surrounding air
D. Charges ionize the surrounding air

Question 35:

• WAEC 2009

An isolated metal sphere of radius R, carrying an electric charge Q, is situated in the medium of relative permitivity, E^r. A test charge is placed at a point p, distance r from the surface of the sphere. Let E^o represent the permitivity of free space. The electric potential at p is given by the expression

A. \(\frac{Q}{4 \pi E_o E_r}\)
B. \(\frac{Q}{4 \pi E_o E_r (R +r)}\)
C. \(\frac{Q}{4 \pi E_o E_r(R - r)}\)
D. \(\frac{Q}{4 \pi E_o E_rR}\)