Physics 1992 Waec Past Questions and Answers

Question 51 :

• WAEC 1992

What is the electric potential at a point distance r from a proton of charge q placed in a medium of permittivity ε_o?

A. Q²/4πε_or²
B. Q/4πε_or²
C. Q²/4πε_or
D. Qr/4πε_o
E. 4πε_oq²r

Question 52 :

• WAEC 1992

lf the frequency of the a.c. circuit illustrated is 500Hz/ π what would be the reactance in the circuit?

A. 0.01Ω
B. 190.91 Ω
C. 200.00 Ω
D. 795.46 Ω
E. 1000.00Ω

Question 53 :

• WAEC 1992

Which of the following statements is correct about cathode rays? They are fast moving

A. Atoms
B. Ions
C. Neutrons
D. Protons
E. Electrons

Question 54 :

• WAEC 1992

Which of the following gives rise to the line spectra obtained from atoms?

A. Kinetic energy of a moving atom
B. Potential energy of an electron inside an atom
C. Change of an electron from a higher to a lower energy level in the atom
D. Disturbed proton in the nucleus
E. Excitation of an electron in the atom

Question 55 :

• WAEC 1992

A stream of alpha particles is projected into an electric field between two plates X and Y as shown in the diagram above. Which of the following is correct? The particles are

A. Accelerated and they continue in a straight line
B. Directionally reversed at the end of the plates
C. Deflected towards plate Y
D. Attracted by both plates
E. Deflected towards plate X.