Electrical Principles Paper 1

Which of the following statements is NOT true:

• Work done is equal to force x distance.

• Watts equal amps divided by volts.

• Energy used is equal to work done.

• Power is the rate at which energy is converted.

The resistivity of an electrical conductor depends on its:

• length divided by its cross-sectional area.

• material.

• length.

• cross-sectional area.

The electrical energy generated by power stations is transferred to the national grid by means of:

• voltage amplifiers.

• generators.

• power boosters.

• transformers.

Which one of the following methods does not use a fossil fuel to generate electricity:

• nuclear

• coal fired

• gas fired

• oil fired

The SI unit of mass is the:

• kilogram.

• Newton.

• tonne.

• joule.

A series circuit consists of three resistors with values of 100Ω, 250Ω and 350Ω. The total resistance is:

• 550Ω

• 550?

• 700Ω

• 700?

The meter used in an electrical installation for recording the energy used is called:

• a wattmeter.

• an ammeter.

• a kilowatt hour meter.

• a power meter.

An electric potential is generated by thermal means when:

• friction occurs.

• a junction of dissimilar metals wires is heated.

• copper wire is heated.

• copper wires are inserted in an electrolyte.

Which of the following makes use of the magnetic effect of an electric current:

• an electromagnet.

• a bimetal strip.

• a car battery.

• a storage heater.

A coil of wire is placed in a changing magnetic field. If the number of turns in the coil is increased, the voltage induced across the coil will:

• decrease.

• increase inversely to the amount of turns.

• remain unchanged.

• increase.