Q.41)-Who discovered the battery?
- Faraday
- Volta
- Maxwell
- Roentgen
Q.42)-What is the unit of electric power?
- Watt
- Volt
- KWH
- Ampere
Q.43)-Alternating current is converted into direct current by using
- Transformer
- Dynamo
- Rectifier
- Inverter
Q.44)-Fleming Right Hand rule is used to find the direction of
- Alternating current
- Direct current
- Induced current
- Original current
Q.45)-Instrument used to change the speed of electric fan
- Amplifier
- Regulator
- Switch
- Rectifier
Q.46)-Best liquid for the transformer core is
- Stainless steel
- Cast steel
- Hard steel
- Soft iron
Q.47)-Transformer is used for
- To increase the A.C. voltage
- To increase DC. Voltage
- To convert Electric Energy into heat energy
- To convert AC into DC.
Q.48)-The filament of electric bulb is made up of
- Copper
- Nichrome
- Lead
- Tungsten
Q.49)-For the filament of electric bulb tungsten is used because
- It is a conductor
- It is cheaper
- It is malleable
- Its melting point is very high
Q.50)-What is filled inside an electric bulb?
- Nitrogen
- Carbon dioxide
- Argon
- Oxygen