Tamilnadu State Board New Syllabus Samacheer Kalvi 4th Science Guide Pdf Term 1 Chapter 3 Work and Energy Text Book Back Questions and Answers, Notes.

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

Samacheer Kalvi 4th Science Guide Work and Energy Text Book Back Questions and Answers

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

I. Use the correct word to fill the blanks :

(Ramp, Simple machines, Work, Energy, Pulley)

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

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

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

Question 1.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 1
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 2

Question 2.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 3
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 4

Question 3.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 5
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 6

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

III. Match the following :

Question 1.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 7
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 8

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

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

Question 1.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 9
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 10

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

V. Answer the following :

Question 1.
What is the unit of energy?
Answer:
The S.I. 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.

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

Samacheer Kalvi 4th Science Guide Work and 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.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 11
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 12

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

Let us do (Text Book Page No. 104)

Mention whether work is done or not in the following activity.
Question 1.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 13
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 14

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

Try to Answer (Text Book Page No. 109)

Identify and mention the types of simple machines.
Question 1.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 15
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 16

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

Let us do (Text Book Page No. 109)

Complete the table.
Question 1.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 17
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 18

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

Try to Answer (Text Book Page No. 111)

Name the load, effort and fulcrum.
Question 1.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 19
Answer:
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 20

Samacheer Kalvi 4th Science Guide Work and Energy Additional Questions and Answers

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

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

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

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

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

III. Match the following :

Question 1.
Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 work and energy 21
Answer:

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

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

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.
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

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

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

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and energy

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

Samacheer Kalvi 4th Science Guide Term 1 Chapter 3 Work and 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:

Class I lever

Class II lever

1. When the fulcrum is between the effort and the load, it is known as Class I lever. When the load is between the effort and the fulcrum, it is known as Class II lever.
2. Example: scissors, pliers, seesaw. Example: wheel barrow, lemon squeezer, nut cracker.