# Student Resources ## Primary 6 Science Questions on Energy Conversion

In the Topic of P6 science, Energy, students are often asked questions on Energy Conversion. Here are some study tips on how to tackle the topic!

Students are often required to state the energy conversion and also explain the reason behind the energy conversion.

So, what is Energy? Energy is the ability to do work! The work refers to daily activities like walking, running and eating. The work also refers life process such as keeping our hearts beating and blood flowing.

Therefore, without energy, humans cannot live their daily lives!
That’s why Energy is so important!

Let’s have a recap on what the 6 key Forms on Energy! They are:

1. Potential Energy
a. Gravitational Potential Energy
b. Chemical Potential Energy
c. Elastic Potential Energy

2. Kinetic Energy
3. Heat Energy
4. Sound Energy
5. Light Energy
6. Electrical Energy

#### Remember

“Energy cannot be created or destroyed. It can only be converted from one form to another.”

Students learn about Potential Energy and Kinetic Energy in Primary 6. So, we will be focusing on Gravitational Potential Energy and Kinetic Energy!

Gravitational Potential Energy

Gravitational Potential Energy is energy an object possesses due to its position in a gravitational field.

The three Factors that affect the amount of Gravitational Potential Energy in an object are:

1. Mass of the object

The larger the mass of the object , the more Gravitational Potential Energy the object has!

2. Height

The higher the object is from the ground [greater height] , the more Gravitational Potential Energy the object has!

Kinetic Energy

Kinetic Energy is energy an object possesses due to its motion.

The two Factors that affect the amount of Kinetic Energy in an object are:

1. Mass of the object

The larger the mass of the object, the more Kinetic Energy the object has!

2. Speed Of the Object

The higher the speed of the object is travelling in, the more Kinetic Energy the object has!

Let’s take a look at this question on Energy Conversion 1. At which point of the slope, the ball has the greatest amount of kinetic energy?

Energy involved

• Gravitational Potential Energy
• Kinetic Energy

Explanation:

The answer is B because all the Gravitational Potential Energy of the ball is converted to Kinetic Energy of the ball.

When the ball is at Point A, it has the highest Gravitational Potential Energy as it is at its highest point.

As the ball is rolling down from Point A to B, more and more Gravitational Potential Energy is converted to Kinetic Energy until the ball reach Point B where all the Gravitational Potential Energy is converted to Kinetic Energy.

#### Tip:

The lowest point always has the most Kinetic Energy

2. Write the energy conversion of the tennis ball from point A to C?

Energy involved

• Gravitational Potential Energy
• Kinetic Energy
• Sound Energy
• Heat Energy

Gravitational Potential Energy of the ball at A is converted to Kinetic Energy of the ball at B which is converted to Gravitational Potential Energy and Kinetic Energy of the ball at C. The Gravitational Potential Energy and Kinetic Energy at Point C is loss to Sound Energy and Heat Energy until it comes to a stop at Point D where all energy loss to Heat and Sound energy.

Explanation:

• As mentioned before, the Gravitational Potential Energy of the ball from Point A is converted to Kinetic Energy at Point B.
• As the Ball move up to Point C, some of Kinetic Energy is converted back to Gravitational Potential Energy.
• Finally, when the Ball move from Point C to D, the Kinetic Energy of the ball is converted to Sound Energy and Heat Energy as the balls comes to a stop at D.

#### Tips:

Explain why the ball stop! Kinetic Energy is lost to Heat/Sound/Heat and Sound/Other forms of energy

If the ball has come to a complete stop, use ALL Kinetic Energy is converted to other forms of energy.

If the ball is slowing down, use SOME Kinetic Energy is converted other forms of energy

Keywords

• Converted
• The Subject ( ___ Energy of the Ball)
• Gravitational Potential Energy
• Kinetic Energy
• Sound Energy
• Heat Energy