Which physical quantity corresponds to the rate of change of
Force corresponds to the rate of change of momentum.
State the relation between the momentum of a body and the force acting on it.
The rate of change of momentum of a body is directly proportional to the applied force and takes place in the direction in which the force acts.
The SI unit of force is
What is the relationship between force and
Force acting on a body is directly proportional to the acceleration produced in the body.
If the mass of a body and the force acting on it are both doubled, what happens to the
Acceleration remains same since
Name the physical quantity whose unit is ‘newton’.
Newton is the SI unit of force.
Which physical principle is involved in the working of a jet
Jet airplanes work on the principle of conservation of momentum.
Name the principle on which a rocket works.
Rockets work on the principle of conservation of momentum.
Is the following statement true or false :
A rocket can propel itself in a vacuum.
True, because rocket does not require air for obtaining uplift or for burning its fuel.
What is the force which produces an acceleration of 1 m /s2 in a body of mass 1
Mass, m = 1 kg
Acceleration, a =
Force F = m x a = 1
x 1= 1N
Find the acceleration produced by a force of 5 N acting on a mass of 10 kg.
Force F =5 N
Mass m = 10 kg
A girl weighing 25 kg stands on the
The force exerted by the floor on her = the downward force exerted by the girl =250 N
This is due to Newton’s third law of motion which states that to every action there is an equal and opposite reaction.
Name the physical quantity which makes it easier to accelerate a small car than a large car.
Less mass of the small car makes it easier to accelerate a small car than a large car because acceleration is inversely
Fill in the following blanks with suitable words :
(a) To every action, there is an………………….. and…………………… reaction
(b) Momentum is a…………….. Its emit is……………………
(c) Newton’s second law of motion can be written as Force = mass x …………………………… or Force = ……………….. of change of……………….
(d) Forces in
(e) In collisions and explosions, the total ……………… remains constant, provided that no external……………………..
a) Equal; opposite
b) Vector; kg.m/s
c) Acceleration; rate; momentum
d) Magnitude; directions
e) Momentum; force
Explain the meaning of the following equation :
F = m x a
where symbols have their usual meanings
Force is directly proportional to the product of ‘mass’ of the body and the ‘acceleration’ produced in the body by the action of force.
F = m x a
where F is the force applied
m is the mass of the body
a is the acceleration produced in the body
To take the boat away from the bank of a river, the boatman pushes the bank with an oar.
Why does a gunman get a jerk on firing a
Gunman gets a jerk on firing a bullet because when a bullet is fired from a gun, the force sending the bullet forward is equal to the force sending the gun
If action is always equal to
To make the cart move, the horse bends forward and pushes the ground with its feet. When the forward reaction to the backward push of the horse on the ground is greater than the opposing frictional forces of the wheels, the cart moves.
|1. What is the force and law of motion?
|2. How many laws of motion are there?
|3. What is the relationship between force and motion?
|4. Give an example of Newton's third law of motion.
|5. How does the law of motion apply to everyday life?