Q3.

Consider the following statements regarding performance indices of a solar collector : 

1. Temperature range is the range of temperature to which the heat transporting fluid is heated up by the collector. 

2. Collector efficiency is defined as the ratio of the energy actually absorbed and transferred to heat transporting fluid by the collector to the energy incident on the collector. 

3. Concentration ratio is defined as the ratio of the area of the receiver to the area of aperture of the system. 

Which of the above statements are correct?

Q4.

Consider the following statements regarding solar thermal systems : 

1. In cold climate regions, large amount of low-grade thermal energy is required for heating air for comfort. 

2. Solar energy is best suited for low-grade thermal applications. 

3. Solar thermal energy is not utilized in drying industries. 

Which of the above statements are correct?

Q5.

Consider the following statements regarding chemical energy storage : 

1. The chemical energy in hydrogen can be converted into thermal energy.

 2. Hydrogen-fired steam turbine may also be used to obtain mechanical energy.

 3. Electrical energy may also be obtained more efficiently directly from hydrogen by means of fuel cell. 

Which of the above statements are correct?