1993 - WAEC Physics Past Questions and Answers - page 4

The unit of inductance is

A household refrigerator consumes electrical energy at the rate of 200 W. lf electricity costs 5 k per kWh, calculate the cost of operating the appliance for 30 days.

Calculate the escape velocity of a satellite launched from the earth’s surface (Take g as 10ms^-2 and the radius of the earth as 6.4 x 10⁶m)

What is the gravitational potential due to a point mass m at a distance from it? (G = gravitational constant)

In a series R - C circuit, the resistance of the resistor is 4 Ω and capacitive reactance is 3 Ω. Calculate the impedance of the circuit

The vector diagram shown below represents the resistance R, the capacitive reactance X_c, the inductive reactance X_c and the impedance, Z in an R-L-C circuit. The current in the circuit will be maximum when

In a purely resistive a.c. circuit, the current I = I_o sin wt and voltage, V = V_o sin wt. Calculate the instantaneous power dissipated in the circuit in time t.

A point charge of 1.0 x 10^-7 C experiences force of 0.01 N in a uniform electric field. Calculate the magnitude of the strength of the field

The potential difference between two points A and B situated at a distance d apart is V. Which of the following expresses the magnitude of the electric field intensity between the two points assuming the field is uniform?

Which of the following have the greatest penetrating power?