Energy
1. Recall four types of energy? Four types of energy include Gravitational,
Elastic, chemical and nuclear energy.
2. Identify the type of energy?
a. When a person is running they are using Kinetic energy.
b. When a spring is stretched it is using elastic energy.
3. Use a suitable example to describe what is meant by an Energy
transfer?
a. An energy transfer is when it is transferred to one object or material to
another. Energy is transferred from a wall socket to battery inside a
phone.
b. An energy transformation is when one energy is transferred to the
other. AN example of this is pole vault.
4. Outline the Law of Conservation of energy?
The conservation of energy is when the energy is isolated and cannot
change.
5. Identify the different types of energy involved in a trampoline jump?
The different types of energy that is used in a trampoline jump is elastic
potential energy, kinetic energy gravitational potential.
6. Imagine riding your bike along a flat gravel road. If you brake
suddenly, the bike eventually stops. It no longer has kinetic energy.
However, the energy is not lost. Describe what happens to the
kinetic energy? The kinetic energy is changed into sound energy when
you brake.
7. A saucepan of water is heated to boiling on an electric hotplate. For
this situation, list three examples of the ways that energy is
transformed or transferred?
Three examples of ways that energy is transformed or transferred. While
heating water is the electrical energy transformed to heat energy, then
transferred into the saucepan then to water, which then evaporated.
8. Calculate the gravitational potential energy of a 2kg cat sitting on a
tree branch 15 metres from the ground?
The gravitational potential energy of a 2kg cat sitting on a tree branch 15
meters from the ground 2x10m/s2x 15=3000joules.
9. Calculate the Kinetic energy of a 60kg sprinter running at 8m/s.
The Kinetic energy from a 60kg sprinter running at 8m/s
1/2x60kgx8m/s=240joules.
10. A child siting at the top of a playground slide has 2000joules of
kinetic energy. She flies off the end of the slide with 1200 joules of
kinetic energy.
a. Calculate the amount of energy transformed to types of energy
other than kinetic energy.
There are two other types of energy transformed, which are
Gravitational and sound.
b. Suggest what these other energy types may be.
Sound as she hits the ground and gravitational as she is elevated in the
air.