Class 8 Science Force and Pressure important notes

Last updated on June 28th, 2023 at 11:08 pm

Class 8 force and pressure important notes

 

Get up to speed with force and pressure topics in Class 8 with these comprehensive, easy-to-understand notes. Learn the key concepts, definitions and formulas quickly and easily. Boost your grades and ace your exams with these helpful study materials.

Fill in the blanks related to force and pressure for class 8:

 

1. Force is a _______ or a _______ that can change the state of motion or shape of an object.
2. Contact forces occur when two objects are in _______.
3. Non-contact forces act over a _______.
4. Force is measured in units of _______.
5. Pressure is defined as the amount of force applied per unit _______.
6. Pressure can be calculated by dividing force by the _______ on which it is applied.
7. The si unit of area is square _______.
8. The pressure exerted by a liquid depends on its _______ and the density of the liquid.
9. The atmospheric pressure is measured using a device called a _______.

 

Answers:

1. Push, pull
2. Contact
3. Distance
4. Newtons (n)
5. Area
6. Area
7. Meters (m²)
8. Depth
9. Barometer

 

True/false of force and pressure

 

• Friction is a non-contact force. False.
• Gravity is an example of a non-contact force. True.

Reason – gravity is a force that acts at a distance between two objects.

• Pressure is defined as the amount of force applied per unit area. True.
• The si unit of pressure is pascal (pa). True.
• The pressure exerted by a liquid depends on its depth and the density of the liquid. True.
• The atmospheric pressure is the pressure exerted by the weight of water in the atmosphere. False.

Reason – the atmospheric pressure is the pressure exerted by the weight of air around us.

• Pascal’s law states that pressure applied to a fluid is transmitted uniformly throughout the fluid. True.
• The hydraulic system is based on archimedes’ principle. False.

Reason – the hydraulic system is based on pascal’s law.

• Pressure and force are the same thing. False.

Reason – Pressure and force are different physical quantities.

 

Important points from the chapter force and pressure for class 8:

 

Force is a physical quantity that changes the state of motion of an object or changes the shape of an object. It is measured in newtons (n). Force is a push or a pull that can change the state of motion or shape of an object.

Pressure is defined as the amount of force applied per unit area. It is measured in units of pascals (pa).pressure can be calculated by dividing force by the area on which it is applied. I.e., pressure = force / area.

The si unit of area is square meter (m²).

The pressure exerted by a liquid depends on the depth of the liquid and the density of the liquid.

Atmospheric pressure is the pressure exerted by the weight of the air around us. It is measured using a barometer.