Third Law of Motion
State the principle of conservation of linear momentum.
KE of a system can be increased without applying any external force to the system.
Why action and reaction do not cancel out each other?
APPLICATION OF SECOND LAW OF MOTION :
In high jump events, why the athlete is made to jump on a cushioned bed ?
The action and the reaction force act on two different bodies. True or false?
A book is kept on the table top and is at rest. The force which acts on the book is
What does action-reaction force mean?
When a carpet is beaten with a stick, dust comes out of it. Explain why this happens? [2 MARKS]
According to Newton's third law of motion, the action and reaction always act on:
The same body.
The same body and in the same direction.
According to the third law of motion, action and reaction
always act on the same body
always act on different bodies in opposite directions
have same magnitude and directions
act on either body at normal to each other
Give two examples from everyday life where the Newtons third law of motion comes into play?
Explain how inertia is used to dust a floormat and to remove water drops from a wet cloth. [3 MARKS]
One gram force is equal to 10 N
The magnitude of force that the earth exerts on the moon is the same as that of the force that the moon exerts on the Earth.
Give information about commonly used gadgets or devices which are based on the principles of newtons laws of motion.
If an external force acts on a system, can momentum be conserved?
Use Newton's laws of motion to explain the flying of an aeroplane ?
The action and the reaction force act on two different bodies.
According to Newton's third law of motion- "Every action has an equal and opposite reaction".
Statement 1: For every interaction, there is a pair of forces acting on the two interacting objects.
Statement 2: The magnitude of the force on the first object equals the magnitude of the force on the second object.
Statement 3: Forces always come in pairs - equal and opposite action-reaction force pairs.
Statement 4: Action and its reaction act on the same bodies.
Statement 5: Action and its reaction act on two different bodies.
- All statements except 4 can be inferred from 3rd law of motion
- Only statement 1 can be inferred from 3rd law of motion
- All statements except 5 can be inferred from 3rd law of motion
- All statements can be inferred from 3rd law of motion
Action and reaction force are equal in magnitude but opposite in direction.
A truck starts from rest and rolls down a hill with a constant acceleration. It travels a distance of 400 m in 20 s. Find its acceleration. Find the force acting on it if its mass is 7 metric tons (Hint: 1 metric ton = 1000 kg).
The flight of a bird is associated with which Newton's law of motion. Give a suitable example to justify your answer.