# The different Forms of Energy

## STUDENT ‘S LEARNING OUTCOME

• Demonstrate the different forms of Energy.
• Define the Heat.
• Define the Light.
• Define the sound.
• Differentiate between transparent, translucent and opaque objects.

### INFORMAATION FOR TEACHER

Teacher knows:

• What is the Energy? Force or Vigor expression
• Forms of energy.
• Heat, light and sound are different forms of energy.

HEAT

• Heat keeps the things warm. By heating solids change into liquid and liquid into gas.

LIGHT

• Light helps us to see. Light travels in a straight line

SOUND

1. To blow, to strike and to shake are such actions which produce sounds.
2. Sound is produced by vibrations.

Transparent  objects

• Bodies, through which light completely passes are called transparent objects.

Translucent objects;

• Bodies, through which light can partially pass, are called translucent objects.

Opaque objects;

• Bodies, through which light cannot pass at all are called opaque objects.

### MATERIAL REQUIRED

Sprit lamp, match stick, piece of ice, candles, cardboards, torch, bell

### DEVELOPMENT

Activity: 1

• Put some ice pieces in a pot and heat it by a spirit lamp.

→   What is the effect of heat on ice?

→   Has the ice changed into water?

• Now heat the water more;

→   Does any change now occur due to heat?

→   Does the water start taking the form of steam?

• Yes steam starts coming out of water and increases slowly and at last the whole of the water is changed into steam.
• By heating a change can be produced in the state of matter i.e. solid on heating change into liquid and liquid when heated changes into gas.

Activity: 2

• Take three similar cardboards. Make holes in all these at the same height. Keep them in a straight line near the edge of the table as shown in the figure. Light the candle on one side of the cardboard and try to see it from the other side.

→   Do you see the flame?

• Now move any one of these cardboards on the left or right side.

→   Do you still see the flame?

→   If your answer is in negative, then why does this happen so?

• Light travels in a straight line. If any obstacle comes on the way, it stops there.

Activity: 3

• Strike the bell with iron rod.

→   Do you hear any sound?

• Touch the bell.

→   Do vibrations also produce in it?

• SOUND IS PRODUCED BY VIBRATIONS.

### ASSESSMENT

• Give the students following questions and ask them to tell the answer individually.

→   What is the effect of heat on ice?

→   Has the ice changed into water?

• Now heat the water more.

→   Does any change now occur due to heat?

→   Does the water start taking the form of steam?

→   Do you see the flame?

• Now move any one of these cardboards on the left or right side.

→   Do you still see the flame?

• If your answer is in negative, then why does this happen so?
• Strike the bell with iron rod.

→   Do you hear any sound?

• Touch the bell.

→   Do vibrations also produce in it?

### FOLLOW UP / HOME WORK

• Write these questions on the board and ask the students to note down on their note books.

WHAT IS ENERGY?

(Students’ response: Force or vigor of expression.)

Forms of energy;

(Students’ response: Heat, light and sound is different forms of energy.)

HEAT;

(Students’ response: Heat keeps the things warm. By heating solids change into liquid and liquid into gas.)

LIGHT;

(Students’ response: Light helps us to see. Light travels in a straight line)