Figure 4 shows identical beakers P and Q full of water at #90^0C#. Two similar cold wet clothes are wrapped, one around the top of P and the other around the bottom Q.

State with a reason the beaker in which the water cools faster.

Answer:

- Beaker P. Cool layers from the top descend and are replaced by hotter layers. Convection currents are set up. In Q, the cool layer of the water remains at the bottom and
thus no convection currents are set up.

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State with a reason the beaker in which the water cools faster.