Tag: generation of electricity

Questions Related to generation of electricity

Which colour is the interior of solar cooker?

  1. White

  2. Black

  3. Purple

  4. Yellow


Correct Option: B
Explanation:

Interior of the solar cooker is painted black inorder to absorb maximum of the Sun's light falling on the device.

Which is NOT an advantage of solar cooker?

  1. It has no moving parts.

  2. It requires a lot of maintenance.

  3. It can be used in remote areas.

  4. It does not cause any pollution.


Correct Option: B
Explanation:

Solar panel is a very useful device. Some of its major advantages are:

1. As it has no moving parts during operation, energy loss due to friction is absent.
2. It can be used in any region where there is sufficient sunlight.
3. It does not cause any pollution and produces no byproducts.

The disadvantage with solar cooker is that it requires a lot of maintenance. The mirrors and the glass need to be kept clean. The orientation of mirrors need to be changed at regular times in a day as sun changes its position.

A solar water heater cannot be used to get hot water on:

  1. a sunny day.

  2. a cloudy day.

  3. hot day.

  4. windy day.


Correct Option: B
Explanation:

Solar devices are dependent on the sunlight for the generation of electricity. For the solar device to work efficiently, sunlight with good intensity should be available. Sunlight is weak during cloudy and rainy days. 

Which of the following devices convert solar light to electricity?

  1. Wind mills

  2. Turbines

  3. Thermostat

  4. Solar Panels


Correct Option: D
Explanation:

Solar panels are used to convert light (from solar energy) into electricity.

Wind mills harness wind energy to generate electricity.
Turbines are used in dams, which help in utilizing the kinetic energy of water in rivers.
Thermostat is a device used for maintenance of constant temperature. It is not used for energy production.  

Which ones are uses of solar panels?

  1. used in satellites and mars probe

  2. used in traffic signals

  3. used in calculators and toys

  4. All of the above


Correct Option: D
Explanation:

Solar panels can be used in calculators and battery operated toys, in satellites and Mars probes to provide them with energy to function in outer space by using the Sun's rays, can be used in traffic signals etc.

State whether the given statement is True or False :
Solar panels can produce electricity throughout the year. 
  1. True

  2. False


Correct Option: B
Explanation:

Solar panels are dependent on the sunlight for the generation of electricity. For the solar panels to work efficiently, sunlight with good intensity should be available to fall on the panels. Sunlight is weak during cloudy and rainy days. Hence, solar panels cannot produce energy throughout the year.

What is estimation of solar constant?

  1. 1.4 kW per square meter

  2. 1.4 W per square meter

  3. 1.6 kW per square meter

  4. 1.4 kW per square centimeter


Correct Option: A
Explanation:

Solar constant is defined as the mean amount of the solar energy received by the Earth's atmosphere, per unit of the area, during the time when the Earth is at the mean distance from the Sun. Solar constant equals to 1388 watts per square meter.

Which of the following element is used in making solar cells?

  1. Gold

  2. Carbon

  3. Silicon

  4. Silver


Correct Option: C
Explanation:

Solar cells are devices that converts Sun's radiation energy into electricity. Solar cells contains a semiconductor. Silicon is a good semiconductor that can be used for the production of solar cells.

A solar water heater cannot be used to get hot water on

  1. a sunny day

  2. a cloudy day

  3. a hot day

  4. a windy day


Correct Option: B
Explanation:

A solar water heater cannot be used to get hot water on a cloudy day as there is no Sun which is necessary for the working of solar water heater.