Explanation:
The planet Mars has two moons. Phobos and Delmos (i) phobos has period `7` hours, `39` minutes and an orbital radius of `9.4 xx 10^(3) km`. Calculate the mass of Mars. (ii) Assume that Earth and mars move in a circular orbit around the sun, with the martian orbit being `1.52` times the orbital radius of the Earth. What is the length of the martian year in days? `(G = 6.67 xx 10^(-11) Nm^(2) kg^(-2))`
The energy that can be renewed again and again is known as renewable source of energy. Example : water, sunlight, wind et cetera.
The energy cannot be created again,once destroyed is known as non renewable source of energy.
The energy obtained from coal is non-renewable.
Energy obtained from burning plant waste is renewable
Energy obtained from water spring inside the earth is renewable.
Energy obtained from natural gas is non renewable.
That we all came from a common ancestor.
