Electricity & Magnetism MCQs with Answers

Spinning electron creates ?

• A.Electromagnetic wave
• B.Electric current
• C.Gravitational field
• D.Magnetic field

The condition of fully charged battery in lead acid battery can be ascertained by ?

• A.Color of the electrolyte
• B.Specific gravity of the electrolyte
• C.Voltage of the battery
• D.All of these

Electric device that converts AC to DC is called _?

• A.Rectifier
• B.Inverter
• C.Transformer
• D.Oscillator

What should be the effect on load, if the frequency of electricity is doubled?

• A.Increases the efficiency
• B.Decreases the efficiency
• C.No effect on efficiency
• D.Efficiency becomes zero

The substances which can be strongly magnetized are called _?

• A.Paramagnetic
• B.Diamagnetic
• C.Ferromagnetic
• D.Non-magnetic

The mechanical energy spent by the external agency is converted into electrical energy stored in the coil. This relates to?

• A.Faraday's law
• B.Lenz's law
• C.Ohm's law
• D.Joule's law

An inductor can store energy. This energy is stored in ?

• A.Electric field
• B.Electrostatic field
• C.Gravitational field
• D.Magnetic field

The terminal voltage of a generator changes due to ?

• A.Armature resistance
• B.Field current
• C.Load resistance
• D.Speed of rotation

Which statement describes the electrical potential difference between two points in a wire carrying a current?

• A.The product of the current and the resistance between the points
• B.The ratio of the power dissipated between the points to the charge moved
• C.The product of the power dissipated and the time taken
• D.The ratio of the resistance between the points to the current flowing

Pure water does not conduct electricity because it ?

• A.Is almost unionized
• B.Contains no dissolved salts
• C.Is a covalent compound
• D.Has low density