Force, Work and Energy - Class 4 Science - New St. Mery English School

Understand the basics of Force, Work and Energy with this easy and child-friendly Class 4 Science lesson. Learn what force is, types of forces like push, pull, muscular force, gravitational force, and friction, and how they affect objects around us. This lesson also explains what work is, when work is said to be done, and the different forms of energy such as heat, light, and motion. Perfect for CBSE Class 4 students, teachers, and parents looking for simple, clear, and well-explained science notes. 

Force, Work and Energy - Class 4 Science - New St. Mery English School

What is Force?

Ans:- Force is a push or pull on an object that can change its state of motion or shape. Force makes things move, stop, speed up, slow down, change direction, or change shape.

Write five effects of Force.

Ans:- The five effects of force are

1- It can move an object.

2- It can stop a moving object.

3- It can change the speed of moving object.

4- It can change the shape of an object

5- It can change the direction of a moving object.

How many types of force?

Ans:- There are many different types of forces, Some of them are

1- Muscular Force

2- Gravitational Force

3- Magnetic Force

4- Friction Force

What is Muscular Force?

Ans:-  The force that we apply using our muscles is called Muscular Force.

Ex:- Lifting a school bag, Kicking a football, Pushing a table, Riding a bicycle, Cutting vegetables with hands

What is Gravitational Force?

Ans:- Gravitational force is the force that pulls everything down toward the Earth.

Ex:- When you drop a ball, it falls down, Leaves fall from trees to the ground, Water flows downward

What is Magnetic Force?

Ans:- Magnetic force is the force by which a magnet attracts or repels certain objects. A magnet mainly attracts objects made of iron, nickel, or cobalt. These are called Magnetic substance.

Ex:- A magnet attracting pins or paper clips, A fridge magnet sticking to the refrigerator, A magnet pulling iron nails 

What is Friction Force?

Ans:- A force that slows down or stops a moving object is called Friction Force. It works between two surfaces which are in contact. Friction force is more on rough surface and less on smooth surface.

Ex:- When you rub your hands together, they become warm due to friction., We erase pencil marks on paper using friction.

Write five advantage of friction.

Ans:- The five advantage of friction are

1- Friction Helps us to stand, walk and run

2- Friction Helps vehicles move.

3- Friction Helps us in writing.

4- Friction Helps to stop moving objects.

5- Friction Helps us to hold things.

Write five disadvantages of friction.

Ans:- The five disadvantages of friction are

1- Friction produces heat that causes wear and tear of machines.

2- Friction tears the soles of shoes.

3- Friction Makes movement difficult.

4- Friction Wastes our energy.

5- Friction Reduces efficiency there for machines do not work smoothly.

What is work?

Ans:- Work is said to be done when a force is used to move something.

If you push, pull, lift, or carry an object and it moves, then work is said to be done.

Ex:- Pushing a table and it moves, Pulling a bucket from a well, Kicking a football and it rolls

What is Energy?

Energy is the ability to do work. We need energy to do all activities like walking, running, playing, reading, lifting things, and even breathing.

How many types of energy?

Ans :- There are many different types of energy, Some of them are

1- Solar Energy

2- Wind Energy

3- Hydro Energy

4- Fuel energy

What is solar energy?

Ans:- The energy that we get from sun is called solar energy.

Write three uses of solar energy.

Ans:- Three uses of solar energy are

1- Plants make food in the presence of solar energy.

2- Solar Energy is used to cook food using solar cooker.

3- Solar energy is converted into Electric energy using solar cell.

What is wind energy?

Ans:- The energy that we get from moving energy is called Wind Energy.

Write three uses of wind energy.

Ans:- The three uses of wind energy are

1- Wind energy is used to sail a boat.

2- Wind energy is used to run a wind mill.

3- Wind energy is used to generate electricity with the help of wind mill.

What is Hydro Energy?

Ans:- The energy that we get from moving water is called Hydro Energy.

Write an use of Hydro Energy.

Ans:- Hydro Energy is used to generate electricity.

What is Fuel Energy?

The energy that released by fuel like coal, LPG, kerosene, petrol, diesel and CNG is called fuel energy.

Write an use of Fuel Energy?

Ans:- Fuel energy is used to run machines and vehicles.