A solar power plant operates on a standard ideal cycle with Refrigerant-134a as a working fluid. R-134a enters the turbine at a rate of 0.05 m3/s, 18 bar and leaves the turbine at 7 bar. The rate of energy input to the collectors from solar radiation is 0.3 kW per m2 of collector surface area, with 60% of the solar input to the collectors absorbed by the refrigerant as it passes through the collectors in the boiler. Determine (a) The solar collector surface area (5003 m2) (b) The thermal efficiency of the power plant (9.4%)

D: The Sun and the planet attract each other with their gravitational forces.

B:The planet speeds by the Sun with a lot of momentum.

A: The planet continues to move forward due to momentum, while the Sun’s gravity pulls the planet back.

C: The planet moves along a closed orbital path around the Sun.

Explanation:

There are 8 planets in the solar system which revolve around the sun in an elliptical orbit with sun at one of its focii. The planets are bound in the orbits around the Sun due to gravitational pull.

The Sun being heavier, the planets speeds by it with a lot of momentum. As the planet continues move forward due to momentum, the sun pulls back them due to gravity. Then, the planets move along a closed orbital path around the sun.