Question

Match the situation with the energy transformation ITEMBANK: Move to Top A boy shooting a rubber band across the classroom A child going down a slide on a playground Rubbing your hands together to warm them on a cold day Turning on a battery operated light Using a dc electric motor Using a gas power heater to warm a room Using a hand crank generator to produce electric current Using the light in your room that is plugged into the wall Chemical potential energy transformed into radiant energy Gravitational potential energy transformed into kinetic energy Elastic potential energy transformed into kinetic energy Chemical potential energy transformed into thermal energy Electrical energy transformed into radiant energy Kinetic energy being transformed into thermal energy Electrical energy transformed into kinetic energy

Answer 1

A boy shooting a rubber band across the classroom --> 
Elastic potential energy transformed into kinetic energy 
The initial energy is the energy stored in the muscles of the boy's arm, which is elastic potential energy. This is converted into motion of the rubber, therefore kinetic energy

A child going down a slide on a playground --> Gravitational potential energy transformed into kinetic energy 
On top of the slide, all the energy of the child is gravitational potential energy due to its height with respect to the ground (E=mgh). when it moves down the slide, this is converted into kinetic energy, because the child acquires a speed v (E=1/2 mv^2)

Rubbing your hands together to warm them on a cold day --> Kinetic energy being transformed into thermal energy 
When rubbing hands, we are moving them (kinetic energy), and this energy raises the temperature of the hand's surface (thermal energy)

Turning on a battery operated light --> 
Chemical potential energy transformed into radiant energy 
A battery works by mean of chemical reactions (chemical potential energy), producing light (so, emitting energy by radiation, i.e. radiant energy)

Using a dc electric motor -->  Electrical energy transformed into kinetic energy
A dc electric motor works using  currents (so, electrical energy), and the energy produced can be used for example to accelerate a car (kinetic energy)

Using a gas power heater to warm a room --> Chemical potential energy transformed into thermal energy 
A gas power heater burns gases (so, chemical reaction, i.e. chemical potential energy) to raise the temperature of the room (thermal energy)

Using a hand crank generator to produce electric current --> Kinetic energy transformed into electrical energy
In a hand-crank generator, the handle is being rotated (kinetic energy) in order to produce an electric current (electrical energy)

Using the light in your room that is plugged into the wall --> Electrical energy transformed into radiant energy  
The lamp works by using electrical current flowing into a resistor (electrical energy) and it produces light, so it emits energy by electromagnetic radiation (radiant energy)