Class 9 (Science Assignment)

 

Passage: Force and Motion

Force and motion are important concepts in physics that explain how objects move and change their state. Force is a push or pull acting on an object. It can change the speed, direction, or shape of an object. For example, pushing a football makes it move, and applying brakes on a bicycle slows it down.

Motion is the change in position of an object with time. An object can have different types of motion, such as linear motion, circular motion, and rotational motion. The motion of an object depends on the forces acting on it.

According to Newton’s first law of motion, an object remains at rest or continues moving at a constant speed in a straight line unless an external force acts on it. This property is called inertia. For example, passengers in a moving bus move forward suddenly when the driver applies brakes because their bodies tend to maintain their previous motion.

The relationship between force, mass, and acceleration is explained by Newton’s second law of motion. A greater force produces greater acceleration, while a heavier object requires more force to produce the same acceleration.

Questions                                                                                     

1. What is force? Give one example of force from daily life.

2. What is meant by motion? Name any two types of motion.

3. Explain Newton’s first law of motion with the example of passengers in a bus.

4. Numerical Question:
A force of 20 N acts on an object of mass 5 kg. Calculate the acceleration produced in the object.

5.     Scientific Reasoning Question:
Why does a person wearing a seat belt move less forward when a car suddenly stops?

6.     How does increasing the force affect the acceleration of an object if its mass remains constant?