Unit-1 (BASIC PRINCIPLE IN SOLAR TECHNOLOGY)

The power from the sun intercepted by the earth is approximately

• 1.8 x 10^8 MW
• 1.8 x 10^11 MW
• 1.8 x 10^14 MW
• 1.8 x 10^17 MW

How many minutes does the sun subtend on the surface of the earth?

• 22
• 32
• 42
• 52

Radiation data for solar electric (PV) systems are often represented as

• Kwh/m^ 2
• w/m
• amp/m
• volt

The value of solar constant is

• 1347 W/m2
• 1357 W/m2
• 1367 W/m2
• 1377 W/m2

The percentage variation of the extra-terrestrial flow over a year is approximately

• ± 1.1
• ± 2.2
• ± 3.3
• ± 4.4

Global radiation is a combination of

• Direct radiation – Diffuse Radiation
• Direct radiation + Diffuse Radiation
• Direct radiation / Diffuse Radiation
• Diffuse Radiation / Direct radiation

The global radiation (hrly) reaching a horizontal surface on the earth is given by

• Hourly beam radiation + Hourly diffuse radiation
• Hourly beam radiation – Hourly diffuse radiation
• Hourly beam radiation / Hourly diffuse radiation
• Hourly diffuse radiation / Hourly beam radiation

The function of a solar collector is to convert solar energy into

• Radiations
• Electrical energy directions.
• Thermal energy.
• All of these.

The following is (are) laws of black body radiation

• Plank’s law
• Stefan-Boltzmann law
• Both (A) and (B)
• None of the above

Absorption of solar radiations at earth’s surface occur due to presence of

• Ozone
• Water Vapours
• Carbon di-oxide
• All of the above