Velocity change v time because ACCELERATION=CHANGE IN VELOCITY/TIME
The situation (heat going through the ceiling) describes
conduction ... heat going from one place to another by
soaking through some material.
A). This is the one. Heat goes from from the marshmallow
to your hand by soaking through the wire. This is conduction too.
B). No. The heat in the room goes from the floor to the ceiling
because the warm air rises and carries it there. This is convection.
C). No. There's nothing for the heat to soak through between
the sun and the roof, and nothing that can move from the sun
to the roof and bring the heat with it. This is radiation.
D). No. Cold water sinks from the surface to the bottom because
warm water rose from the bottom to the surface, taking heat with it.
This is convection.
