Text Book Back Questions and Answers - Chapter 3 Work and Energy Term 1 4th Science Guide Samacheer Kalvi Solutions - SaraNextGen [2024-2025]

Updated On May 15, 2024

By SaraNextGen

 Chapter 3 - Work and Energy - Term 1 - 4th Science Guide Samacheer Kalvi Solutions

Text Book Back Questions and Answers
I. Use the correct word to fill the blanks:
(Ramp, Simple machines, Work, Energy, Pulley)

Question $1 .$
______ is said to be done when a force is acting on it.
Answer:
Work

Question $2 .$
The ability to do work is _____.
Answer:
Energy

Question $3 .$

______ is a machine made up of wheel and rope.
Answer:
Pulley

Question $4 .$

______ help us to make work easier.
Answer:
Simple machines

Question $5 .$
An example for inclined plane is _____.
Answer:
Ramp

II. Rearrange the letters and find out the names of the tools:

Question 1.

Answer:

Question 2. 

Answer:

Question 3. 

Answer:

III. Match the following : 
Question 1. 

Answer:

IV. Classify the things below : (Text Book Page No. 109) 
Question 1. 

Answer:

Question $1 .$
What is the unit of energy?
Answer:
The S.l. Unit of energy is the joule.

Question $2 .$
Name some simple machines.
Answer:
Simple machines are pulley, wedge, inclined plane, screw, lever, wheel and axle.

Question $3 .$
What is a first order lever?
Answer:
When the fulcrum is between the effort and the load, it is known as Class I lever. Example: scissors, pliers, seesaw.

Question $4 .$
Lemon juicer belongs to which type of lever? Why?
Answer:
Lemon juicer belongs to Class II Lever. In a lemon squeezer, the lemon (load) is at the middle, the load is at the center of effort and fulcrum.

Question $5 .$
Define work.
Answer:
An action in which one exerts a force to move an object is known as work.

Question $6 .$
Write any three types of energy.
Answer:

- Mechanical energy.
- Thermal energy.
- Chemical energy.

In Text Questions and Answers
Try to Answer (Text Book Page No. 104) .

Observe the picture and put a tick (✓) if work is done and put a cross (x) if work is not done.

Question $1 .$

Answer:

Let us do (Text Book Page No. 104)
Mention whether work is done or not in the following activity.

Question $1 .$

Answer:

Try to Answer (Text Book Page No. 109)
Identify and mention the types of simple machines.

Question $1 .$

Answer:

Let us do (Text Book Page No. 109)
Complete the table.
Question $1 .$

Answer:

Try to Answer (Text Book Page No. 111)
Name the load, effort and fulcrum.

Question $1 .$

Answer:

Additional Questions and Answers
I. Pick out the odd one:
Question $1 .$
Mechanical energy, Heat energy, Chemical energy, Food
Answer:
Food

Question $2 .$
Scissors, broomstick, wrench, sea saw
Answer:
Broomstick

Question $3 .$
petrol, coal, natural gas, water.
Answer:
Water

II. Say true or false:
Question $1 .$
Chemical energy is one of the types of lever.
Answer:
False

Question $2 .$
Simple machines usually exchange a larger force to move a heavy object.
Answer:
False

Question $3 .$
The idea of a simple machine originated with the Greek philosopher Archimedes.
Answer:
True

Question $4 .$
A lever is used to multiply the force.
Answer:
True

III. Match the following : 
Question 1. 

Answer:

1. - (b)
2. - (a)
3. - (d)
4. - (c)

IV. Choose the correct answer :
Question $1 .$
second order lever
(a) Scissors
(b) lemon squeezer
(c) Tongs
Answer:
(b) lemon squeezer

Question $2 .$
Which of the following device converts chemical energy into electrical energy?
(a) Battery
(b) Loud speaker
(c) Solar cell
(d) Electric motor
Answer:
(q) Battery

Question $3 .$
Which among the following is the non-renewable resources?
(a) Sun
(b) Wind
(c) Water
(d) Petrol
Answer:
(d) Petrol

Question $4 .$
SI unit of energy is
(a) Joule
(b) kilogram
(c) Mass
(d) Watt
Answer:
(a) Joule

Question $5 .$
$\mathrm{A}$ is a push or a pull
(a)Force
(b) Friction
(c) Simple machine
(d) pulley
Answer:
(b) Friction

Question $6 .$
Simple machines makes work easier by trading ______ for force.
(a) Motion
(b) Work
(c) Friction
(d) Distance
Answer:
(b) Work

Question $7 .$
A force can cause an object to change its
(a) Shape
(b) Speed
(c) Direction
(d) All the above
Answer:
(d) All the above

V. Fill in the blanks :
Question $1 .$
A _____ should act on an object.
Answer:
Water

Question $2 .$
A pulley is a machine made up of a ______.
Answer:
Wheel

Question $3 .$
______ is used to split materials.
Answer:
Wedge

Question $4 .$
The screw is used to raise ______.
Answer:
Weights

Question $5 .$
The ______ and sharpener are held together by screw.
Answer:
Blade

VI. Answer the following questions in one or two sentences:
Question $1 .$
What is non-renewable resources?
Answer:
The resources which are not easily replaced once used are called the non renewable resources.
Example: Petrol, Coal and Natural gas.

Question $2 .$
Write about Renewable resources.
Answer:
- Renewable sources of energy are replaced naturally over a period of time.
- We can keep using these sources for a long period of time. Since the beginning of human life, we have been using these resources.
- We use these resources for light, transport, cooking, heating. Eg: Sun, Wind and Water.

Question $3 .$
Write the two main conditions are needed for work to be done?
Answer:
Two main conditions are needed for work to be done.

1. A force should act on an object.
2. Object should move from one place to another.

Question $4 .$
What is work?
Answer:
An action in which one exerts a force to move an object is known as work.

Question $5 .$
Define energy?
Answer:
- Energy is defined as capacity for doing work.
- Energy must be transferred to an object in order to do work.

Question $6 .$
Write the type of energy.
Answer:
- Mechanical energy.
- Thermal energy
- Chemical energy
- Electrical energy
- Non-renewable energy
- Renewable energy

Question 7.
What is simple machine?
Answer:
- Simple machines are tools which are used to make our work easier.
- Some examples for simple machines are pulley, wedge, inclined plane,

Question $8 .$
Differentiate Class I lever and Class II lever.
Answer: