Physics

Physics

Energy

• Energy is required to do any kind of work or to produce a force.

• A fuel is an object which is used to produce energy.

• E.g.

• Petrol is the fuel for cars.

• Food is the fuel for humans.

• Wood is the fuel for a fire.

• The different types of energy are heat, light, sound, and electricity.

Quiz Time

Let's all play a quiz

Multiple Choice

Conservation of Energy Questions.

Example: A battery releases 100J of energy to a lamp. The lamp releases 80J of energy as light but it also releases heat energy. How much heat energy is released? Answer=20J ( If he total energy input is 100 and 80 is the output as light, that means that 20 J is left as heat 100J-80J=20J)..Now try these questions..

Question. A battery releases 200J of energy to a lamp. the energy is converted to heat and light. 50kJ is given out as heat. How much is released as Light?

• 100J

• 150J

• 200J

• 250J

Multiple Choice

Complete the statement about the principal of Conservation of Energy.

Energy can be changed for one form to another but the total amount of energy

• always increases

• always decreases

• does not change

• varies according to the reaction

Multiple Choice

The unit of energy is?

• Watt

• Kilojoule

• Kilogramme

• Volt