First Law of Motion

Q. Derive second equation of motion:
$s=ut+\frac{1}{2}a{t}^2$

Q.

Why do you fall in the forward direction when a moving bus brakes to a stop and fall back when it accelerates from rest?

Q.

A fielder in a game of cricket pulls his hands backwards after holding the ball shot by the batsman. This enables the fielder to

1. exert larger force on the ball

2. reduce the force exerted by the ball on hands

3. decrease the rate of change of momentum

4. increase the rate of change of momentum

Q. Newton’s first law of motion is also known as the law of ______ .​

1. Mass
2. Inertia
3. Acceleration
4. Opposing forces

Q.

When a running bus stops suddenly, the passengers tend to fall in the forward direction. This is due to

1. Inertia of motion

2. Inertia of rest

3. Inertia

4. Mass of the bus

Q. Question 4
A motorboat starting from rest on a lake accelerates in a straight line at a constant rate of $3.0m{s}^{-2}$ for $8.0s$. How far does the boat travel during this time?

Q.

How can we describe the position of an object?

Q.

Inertia is the property of a body by the virtue of which the body is unable to change by itself

1. state of rest

2. state of motion

3. both (A) and (B)

4. None

Q. SI unit of Inertia

Q.

What is the effect of force when a ball is hit with a bat ?

Q. The tendency of an object to resist the change in the state of its motion is called ______.

1. mass
2. force
3. frictional force
4. inertia

Q. Two balls of the same size but of different materials , rubber and iron are kept on the smooth floor of a moving
train. Will the balls start rolling ? If so , in which direction ? Will they move with the same speed ? Give
reasons for your answer .

Q. Why does an electric fan continue to rotate for sometime after the current is switched off??

Q.

Why does a ball thrown vertically upwards in a moving train, come back to the thrower's hand?

Q.

Bicycle slows down when we stop pedaling. Because-

1. there is net force on bicycle.

2. there is backward force of friction from the ground.

3. both a) & b).

4. None

Q.

Water sprinkler, used for grass lawns, begins to rotate as soon as the water is supplied. Which of the following laws of motion is the cause of rotation of the water sprinkler?

1. First law of motion due to inertia

2. First law of motion due to motion

3. Third law of motion

4. Second law of motion

Q. Why do we tend to fall outwards when a car takes a steep turn?

Q.

Give qualitative definition of force on the basis of newton's first law of motion.

Q.

Examples of inertia of motion

Q.

Explain the example of the case of horse pulling a cart.

Q.

State and explain the law of inertia (or Newton's first law of motion).

Q.

If there are no external forces acting on an object, it will

1. remain in its state of rest

2. either remain in its state of rest or in uniform motion

3. change its speed

4. move with a higher velocity

Q. If the net force on an object is zero, then the object will ______.

1. accelerate
2. decelerate
3. come to rest
4. be in uniform motion

Q. Why are grooves made on a saucer where the tea cup is placed ? Which law will you use to support your answer?

Q.

Is force needed to keep a moving body in motion?

Q.

Which of the following has more inertia- a rubber ball or a stone of same size? Why?

Q.

When a branch of a tree is shaken vigorously , some leaves drop down. Give reason.

Q. A car of mass 1000 kg moving with a velocity of 20 m/s is brought to rest by applying brakes in 10 seconds. What is the force applied by the brakes?

1. 1000 N
2. 2000 N
3. 4000 N
4. 10000 N

Q.

Which law of Newton is called the law of equilibrium?

Q.

Can a body be in equilibrium if it is in motion$?$