A certain type of decorative lamp contains colored liquids. These liquids form globs that break off and rise to the top of the liquids. The globe rises due to Your

conduction

convection

radiation

Convection

Explanation:

Convection can be defined as the transfer of heat energy from a fluid as hotter materials in the fluid rise up and cooler ones sink down. This results as the hot materials have low density as compared to those which are cold. In the decorative lamp the globs break out as the evaporated form of liquid rises up due to low density and the remaining cold fluid remains at the bottom as a result of convection.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

photocells convert light energy to electricity