Science General · Physics

Energy and Electrical Devices

1,193 Questions

Energy and electrical devices focus on energy conversion, household electrical appliances, batteries, and electric vehicle technology. These principles are essential components of general science syllabi across major competitive examinations. Review these practice questions to strengthen understanding of electrical energy applications and devices.

Energy conversionHousehold electrical appliancesBatteries and cellsElectric vehicles

Energy and Electrical Devices Questions

Multiple choice

In the process of electroplating

  1. electrical energy is converted into chemical energy

  2. electrical energy is converted into heat energy

  3. electrical energy is converted into magnetic energy

  4. all of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Electroplating is an electrolytic process where electrical energy is used to drive a non-spontaneous chemical reaction, converting electrical energy into chemical energy.

Multiple choice

Effect of light on photocells produces

  1. energy

  2. photosynthesis

  3. current

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Photocell is a device in which the photoelectric effect is used to produce a current or voltage when exposed to light or other electromagnetic radiation. 

Multiple choice

Electric Bell works on the principle

  1. Electrical energy is converted into mechanical energy

  2. Electrical energy is converted into sound energy

  3. Mechanical energy is converted into sound energy

  4. Sound energy is converted into electrical energy.

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Electrical energy is converted into mechanical energy

Multiple choice

A thermistor is a type of a

  1. switch

  2. battery

  3. fuse

  4. resistor

  5. power supply
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. The current through a resistor is in direct proportion to the voltage across the resistor's terminals. This relationship is represented by Ohm's law, i.e.V = IRWhere I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms. Option 4 is correct.

Multiple choice

What type of energy transformation takes place in a battery?

  1. Chemical energy to electrical energy

  2. Chemical energy to light energy

  3. Mechanical energy to electrical energy

  4. Mechanical energy to chemical energy

  5. Electrical energy to chemical energy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Battery transforms chemical energy to electrical energy.

Multiple choice

For a gas turbine power plant, identify the correct pair of statements. P. Smaller in size compared to steam power plant for same power output Q. Starts quickly compared to steam power plant R. Works on the principle of Rankine cycle S. Good compatibility with solid fuel

  1. P, Q

  2. R, S

  3. Q, R

  4. P, S
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

(P) Gas turbine power plant consumes less space as compared to stream power plants because in steam power plants accessories like boiler, condenser coding tower adds more size and mass. (Q) Gas turbine power plant can be synchronized very fast as compared to steam power plants take too much time because it took more time to stabilize the temp in boiler. (R) Gas turbine power plants works on Joole-Brayton cycle. (S) Only liquid and gas fuel is used in gas turbine power plants.

Multiple choice

Human body is an example of

  1. isolated system

  2. closed system

  3. adiabatic system

  4. open system
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This system involves the exchange of both matter and energy with the surroundings. Since, human body exchanges both matter and energy with the surroundings, it is an open system.

Multiple choice physics electric current and its effects coil and fuse heating effect of electric current- uses applications of heating effect of electric current

An electric fuse used in households works on which principle of:

  1. Joule's heating

  2. Coulomb's law

  3. Maxwell's law

  4. Ohm's law
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

An electric fuse in households works on the principle of Joule's heating that heat produced due to the excess current flowing through it melts the fuse wire which cut off the circuit and hence the appliance is prevented from damage.

Multiple choice chemistry non-metals dihydrogen fuel dihydrogen as a fuel introduction to hydrogen

In hydrogen economy, energy required for automobiles or electrical energy is obtained from the reaction between _____ and oxygen.

  1. hydrogen

  2. oxygen

  3. silver

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In hydrogen economy, energy required for automobiles or electrical energy is obtained from the reaction between hydrogen and oxygen.
This eliminates the use of carbon based fossil fuels. It reduces emission of carbon dioxide gas. Hydrogen acts as energy carrier as a substitute for petroleum reserves that are in short supply.