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nithinyes

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Consider two 1 square meter marble slabs each of mass 1 kg floating in space facing the sun such that light from the sun incident perpendicularly on the flat faces.

At equilibrium, power received from the sun 'PS' equals the power being lost in the form of radiation 'PR'.

PS = PR (at equilibrium)

For simplicity, assume the equilibrium temperature TE = 300K.

Let us now install a photovoltaic solar panel on the right slab and resistive load on the left slab.

Assume the mass of the photovoltaic panel and resistive load be 1 kg each.

Connect the panel and load using wires and a switch of negligible mass.

Let the new equilibrium temperature also be 300 K.

At time t = 0, the pv cell is connected to the load by closing the switch. Let the power being transmitted from pv slab to load slab be 'PPV' and all this power is consumed by the load slab.

So the net power received by load slab is PS + PPV and the net power received by pv slab is PS - PPV.

Since PS + PPV > PS - PPV,

So what happens to the temperature of the slabs?

PS = PR (at equilibrium)

For simplicity, assume the equilibrium temperature TE = 300K.

Let us now install a photovoltaic solar panel on the right slab and resistive load on the left slab.

Assume the mass of the photovoltaic panel and resistive load be 1 kg each.

Connect the panel and load using wires and a switch of negligible mass.

At time t = 0, the pv cell is connected to the load by closing the switch. Let the power being transmitted from pv slab to load slab be 'PPV' and all this power is consumed by the load slab.

So the net power received by load slab is PS + PPV and the net power received by pv slab is PS - PPV.

Since PS + PPV > PS - PPV,

So what happens to the temperature of the slabs?

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