Ametal bar is used to conduct heat. when the temperature at one end is 100°c and at the other is 20°c, heat is transferred at a rate of 16 j/s.

if the temperature of the hotter end is reduced to 80°c, what will be the rate of heat transfer?
a. 4 j/sb. 8 j/sc. 9 j/sd. 12 j/s

a. 4 J/s

Explanation:

Fourier's law states for the case in which there is stationary heat flow in only one direction, that is, linearly, the heat transmitted per unit of time is proportional to the temperature difference:

When the temperature at one end is 100°C and at the other is 20°C, we have:

If the temperature of the hotter end is , we have:

So:

Finally, we calculate the rate of heat transfer:

explanation:

earth's surface is mainly heated by the absorption of infrared radiation from the sun.

evaporation occurs because molecules in liquid water are warmed ( usually by the sun) and vibrate quicker, becoming less dense and rise.

condensation occurs because molecules in water vapor are cooled and therefore vibrate more slowly thus becoming more dense and eventually fall to earth.

lines of equal barometric pressure on a weather map are called: isobars : lines of equal temp on a weather map are called: isotherms.​

resonant frequency