1. A capacitor of 20x1012F and an inductor are joined in series. The value of the inductance that will give the circuit a resonant frequency of 200KHz is

[π^2 = 10]

2. The magnetic force on a charged particle moving with velocity V is

A working electric motor takes a current of 1.5A when the p.d across it is 250V. if its efficiency is 80%, the power output is

4. A bread toaster uses a current of 4A when plugged in a 240 volts line. It takes one minute to toast slices of bread. What is the energy consumed by the toaster?

5. The cost of running five 60W lamps and four 100W lamps for 20hours if electrical energy costs ₦10.00 per kWh

6. When a piece of rectangular glass block is inserted between two parallel plate capacitors, at constant plate area and distance of separation, the capacitances of the capacitor will

7. A concave mirror of radius of curvature 40cm forms a real image twice as large as the object. The object distance is

8. At what frequency would a capacitor of 2.5μF used in a radio circuit have a reactance of 250Ω?

9. The electric field between two-point charges is shown in the diagram beside.
What types of charges are at X and Y?

10. A current of 0.5A flowing for 3hours deposits 2g of metal during electrolysis. The quantity of the same metal that would be deposited by a current of 1.5A flowing in hours is