Are these practice questions for How Forces Affect Motion based on the CBSE pattern?

Yes. Every practice question is modeled on the CBSE Class 9 Science exam pattern — including MCQs, assertion-reason questions, and short-answer formats that frequently appear in CBSE papers.

Are the practice questions for How Forces Affect Motion free?

Yes. Every chapter includes free practice questions for Class 9 students to get you started.

What types of questions are included?

The practice set for How Forces Affect Motion mainly includes MCQs and CBSE-style short-answer questions, with instant feedback on each answer. For full-length textbook practice, use the NCERT Solutions page.

Are the practice questions suitable for board exam preparation?

Yes. The questions test the same concepts and depth that CBSE asks in board exams. After finishing, also solve the NCERT and NCERT Exemplar exercises for How Forces Affect Motion for full coverage.

How many practice questions are there for How Forces Affect Motion?

The number scales with chapter length and concept density. Each chapter typically has 15-50 practice questions across MCQ and short-answer formats.

How Forces Affect Motion Class 9 Science Practice Questions with Answers

easy

When a cannon fires a cannonball, the cannon recoils. Evaluate why the cannon's acceleration is much smaller than the cannonball's acceleration, even though the forces are equal and opposite.

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easy

Recall Newton's First Law of Motion.

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easy

Define inertia.

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easy

Propose a method for an astronaut floating in space, far from any gravitational influence, to move towards their spaceship if their tether breaks.

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easy

Name the SI unit of force and recall the convention for writing its full name and symbol when named after a person.

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easy

A student states, 'An object with zero net force acting on it must be at rest.' Critique this statement.

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easy

Propose a modification to the design of a racing bicycle's tyres to minimize friction on a smooth track.

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easy

Describe how a spring balance is used to measure the magnitude of a force.

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easy

Examine the net force acting on a bus that is moving along a straight highway at a constant velocity of

60 \text{ km/h}

.

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easy

Define force and list two effects it can have on an object.

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easy

Recall the formula for net force and calculate the net force acting on a block if a force of

12 \text{ N}

pushes it to the right and a force of

8 \text{ N}

pushes it to the left.

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easy

When a rocket expels hot gases downwards, it moves upwards. Examine this phenomenon using Newton's Third Law of Motion.

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easy

A heavy dictionary is placed on a table and remains at rest. Analyze the forces acting on the dictionary to explain why it does not move.

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medium

A cricket player lowers their hands while catching a fast-moving ball. Justify, using the concepts of force, time, and change in momentum, why this action helps prevent injury.

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medium

Summarize Newton's Third Law of Motion. Identify the key characteristic of the pair of forces it describes.

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medium

Design an experiment to verify the relationship that for a constant net force, acceleration is inversely proportional to mass (

a \propto 1/m

). Your design should use a cart, a pulley system, and a method for varying the mass of the cart while keeping the pulling force constant. Describe the variables to be measured and how the data would be plotted to confirm the relationship.

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medium

Describe what happens to an object's motion when the net force acting on it is zero, considering two possible initial states.

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medium

Identify the law of motion that explains why a canoe moves forward when a canoeist pushes water backward with a paddle.

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medium

Two boxes with masses

m_1 = 3

kg and

m_2 = 7

kg are connected by a light string and placed on a frictionless horizontal surface. A horizontal force of

50

N is applied to the

m_2

box. Calculate the acceleration of the entire system.

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medium

A ripe mango falls from a tree towards the Earth. Compare the force exerted by the Earth on the mango with the force exerted by the mango on the Earth. Analyze why only the mango appears to accelerate significantly.

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medium

Two friends push a large crate of mass

100

kg. One pushes with a force of

150

N and the other with

120

N, both in the same direction. If the opposing frictional force is

80

N, calculate the net force acting on the crate.

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medium

Explain the difference between balanced and unbalanced forces. Provide one example for each.

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medium

Compare the acceleration of a

2

kg stone and a

10

kg boulder if both are pushed with an identical net force of

20

N. Calculate the acceleration for each.

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medium

A box of mass

10

kg is pushed with a force of

50

N to the right. The frictional force acting on the box is

15

N. Calculate the net force and the resulting acceleration of the box.

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medium

Analyze how crumple zones in the front of a car help reduce injury to passengers during a head-on collision. Apply Newton's second law of motion in your explanation.

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medium

Explain why it is difficult to walk on a wet, polished floor.

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medium

A net force of

30

N is applied to a stationary object of mass

6

kg. Calculate the velocity of the object after

4

seconds.

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medium

A net force of

20 \text{ N}

acts on an object of mass

m_1

, producing an acceleration of

5 \text{ m/s}^2

. The same force acts on an object of mass

m_2

, producing an acceleration of

2 \text{ m/s}^2

. Formulate an expression for the acceleration produced if the same force is applied to both masses tied together.

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medium

During a collision between a large truck and a small car, a student argues that the force exerted by the truck on the car is greater than the force exerted by the car on the truck, which is why the car suffers more damage. Evaluate this argument based on Newton's laws of motion.

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medium

Create a scenario involving a car of mass

1200 \text{ kg}

where a constant net force is applied, causing it to accelerate from rest. Formulate a problem to find this net force if the car covers a distance of

50 \text{ m}

in

5 \text{ s}

. Then, solve the problem you formulated.

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medium

The velocity of a

1200

kg car changes from

10 \text{ m/s}

to

30 \text{ m/s}

uniformly over a period of

5

s. Calculate the acceleration of the car and the net force that produced this acceleration.

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medium

An elevator is moving upwards at a constant velocity of

2 \text{ m/s}

. A person inside the elevator is holding a bag of mass

5 \text{ kg}

. Justify the net force acting on the bag. (Use

g = 9.8 \text{ m/s}^2

).

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medium

An object has a mass of

20 \text{ kg}

. Recall the formula for force and calculate the net force required to give it an acceleration of

4 \text{ m/s}^2

.

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medium

Describe Newton's Second Law of Motion in terms of force, mass, and acceleration.

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hard

Explain why airbags in cars are a crucial safety feature, using the concepts from Newton's second law.

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hard

A book is resting on a table. A student claims that the gravitational force pulling the book down and the normal force from the table pushing it up are an action-reaction pair according to Newton's third law. Critique this claim.

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hard

Create a problem for a system of two blocks, with masses

m_1 = 3 \text{ kg}

and

m_2 = 2 \text{ kg}

, connected by a light string on a frictionless horizontal surface. A horizontal force

F = 25 \text{ N}

is applied to

m_1

. Propose a method to find the acceleration of the system and the tension in the string. Solve the problem you created.

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hard

Analyze why a person is more likely to slip when walking on a wet, smooth floor compared to a dry, rough floor. Apply Newton's Third Law and the concept of friction in your explanation.

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hard

A rifle of mass

4

kg fires a bullet of mass

20

g (

0.02

kg). The bullet leaves the barrel with an acceleration of

1000 \text{ m/s}^2

. Calculate the recoil acceleration experienced by the rifle.

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hard

A block of mass

5

kg is at rest on a surface where the force of friction is

20

N. A horizontal force of

30

N is applied to the block. Solve for the acceleration of the block and the distance it travels in the first

3

seconds.

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hard

Design an experiment using a spring balance, a wooden block, and various surfaces (e.g., sandpaper, glass, wood) to evaluate the relationship between the nature of the surface and the force of static friction. Describe the procedure, the data you would collect, and how you would interpret the results to justify your conclusion.

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hard

A bird is flying inside a sealed, airtight box which is placed on a weighing scale. Justify whether the reading on the weighing scale will change when the bird takes off from the bottom of the box and hovers in the middle, as compared to when it was resting at the bottom.

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hard

Explain why a falling fruit moves towards the Earth, but the Earth does not appear to move towards the fruit, even though the gravitational forces between them are equal and opposite.

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hard

A satellite orbits the Earth at a constant speed in a circular path. Analyze whether a net force is acting on it and justify your answer by applying the concept of velocity from Newton's first law.

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hard

Design an experiment to evaluate how the acceleration of a toy car on a ramp is affected by the angle of the ramp. Propose a method to calculate the net force acting on the car at a specific angle, considering gravitational force and friction.

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How Forces Affect MotionClass 9 Science Practice Questions