A solar cell converts the sunlight directly into ______________ energy?

Related Mcqs:

1. Direct conversion of thermal energy to electrical energy is facilitated by the____________________?

   A. Fuel cells
   B. Photo voltaic cell
   C. Magneto hydrodynamic generator
   D. None of these

2. A thin, flat & square plate measuring 2 m × 2 m is freely hanging in ambient air at 25°C. It is exposed to the solar radiation falling on one side of the plate at the rate of 500 W/m2. The plate temperature will remain constant at 30°C, if the convective heat transfer co-efficient is ________________ W/m2 °C ?

   A. 50
   B. 100
   C. 150
   D. 200

3. Heat flow across a hollow sphere of inner radius ‘r1’ and outer radius ‘r2’ is directly proportional to__________________?

   A. (r2 – r1)/r1. r2
   B. r1. r2/(r2 – r1)
   C. (r2 + r1)/r1. r2
   D. r1. r2/(r2 + r1)

4. Which one can be directly solidified from gaseous state without entering into liquid state ?

   A. Helium
   B. Oxygen
   C. Carbon dioxide
   D. None of these

5. The Al2O3 content of cryolite in Hall-Heroult cell is maintained between _______________ percent ?

   A. 2-5
   B. 18-20
   C. 12-15
   D. 6-12

6. The cathode in an electrochemical cell always carries____________________?

   A. Negative charge
   B. Positive charge
   C. Zero charge
   D. Positive or negative charge depending upon the nature of the cell

7. The emf of a Deniell cell “Zn | Zn2+ || Cu2+ | Cu” can be increased by_________________?

   A. Decreasing the surface area of the electrodes
   B. Increasing the concentration of zinc sulphate solution
   C. Increasing the surface area of the electrodes
   D. Increasing the concentration of copper sulphate solution

8. Frother is added in the froth floatation cell used in ore beneficiation to stabilise the air bubbles (i.e., froth), which will hold the ore particles, but it does not affect the floatability of minerals. Which of the following is not used as a frother ?

   A. Cresylic acid
   B. Xanthaies
   C. Pine oil
   D. All A, B. & C.

9. Electrolytic reduction cell used for conversion of calcined Al2O3 to Al is a carbon lined furnace operating at 800-900 °C. The purpose of electric current supplied to the furnace is to___________________?

   A. Achieve very high purity of aluminium (99.9%)
   B. Keep the electrolyte in liquid condition by the generation of heat
   C. Electrolytically dissociate alumina
   D. Both B. & C.

10. Internal energy of a gas obeying Van-Der-Waals equation of state, [p + (a/v2)] (V – b) = RT, depends upon its___________________?

    A. Pressure & temperature
    B. Pressure & specific volume
    C. Temperature & specific volume
    D. Temperature only