No.
The acceleration of gravity on or near Earth's surface is 9.8 m/s² ,
not 20 m/s² .
If it were 20 m/s², then you would weigh almost exactly double
what you really weigh now.
Though the hot cocoa would have a higher temperature, the lake would have more thermal energy because it has more molecules with a greater total internal energy.
Melting
we know that ice melts at 0 ⁰C. in the graph, at position B, the temperature is constant, which indicates that phase change is taking place there. at B , from the graph , we also notice that the temperature is constant at value 0 ⁰C. this indicates that ice at 0 ⁰C is converting to water at 0 ⁰C there at position B in the graph.
hence the correct choice is Melting.
The sun produces energy by converting gravitational potential energy into radiation via quantum processes in the nucleus of the atoms.
Since the mass of the sun and it's temperature are not quite enough to generate nuclear FUSION on their own, quantum tunneling is the primary process by which nuclear fusion occurs in our sun, SOL. FISSION also occurs as a result of this fusion.
Additionally, gravitational potential energy is also the reason that supernovae are so bright. Cool!
