Electrical energy is used to spin the blades of a ceiling fan. If the electricity is cut off, the fan blades will slow down and eventually stop spinning. Why?

A.
All the kinetic energy of the fan blades has been transformed into potential energy.

B.
All the potential energy of the fan blades has been transformed into kinetic energy.

C.
All the kinetic energy of the fan blades has been transformed into heat energy.

D.
All the potential energy of the fan blades has been transformed into heat energy.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? question 2 options: the balloons rise at the same rate. both balloons are the same size. the ballons both rise. the cold ballon is larger than the warm balloon. the cold balloon expands and rises. the warm balloon shrinks and sinks. the warm balloon expands and rises. the cold balloon shrinks and sinks.