Activity 11.2 Class 8 Science Chapter 11 Solution

Activity 11.2 Class 8 Science Force and Pressure

In this post, you will find NCERT Science Class 8 Chapter 11 Force and Pressure which consists of a complete explanation. After reading activity 11.1, you should go through the given activity given below.

You are suggested to study NCERT activity 11.2 class 8 science explanation with a conclusion so that you can attempt questions based on activity 11.2 class 8 science.

Activity 11.2 Class 8 Science

    ·      Choose a heavy object like a table or a box, which you can move only by pushing hard.

    ·      Try to push it all by yourself.

    ·       Can you move it?

    ·      Now ask one of your friends to help you in pushing it in the same direction.

    ·      Is it easier to move it now?

    ·      Can you explain why?

    ·      Now push the same object, but ask your friend to push it from the opposite side.

    ·      Does the object move?

    ·       If it does, note the direction in which it moves.

    ·      Can you guess which one of you is applying a larger force?

      

Applying force on the box

Observation and explanation

When the box is pushed by a single person, it is difficult to be pushed.

When two persons apply force on the box in the same direction, the magnitude of the applied force becomes double, in this case, the box moves easily.

When two persons apply a force of similar magnitude on the box in opposite directions, the resultant force becomes zero, so the box doesn’t move.

On the other hand, when two persons apply forces of different magnitudes on the box, the box moves in the direction of the larger force.

So the magnitude of the force is the important factor.

Conclusion 

Activity 11.2 shows that the strength of the force is expressed by its magnitude.

Frequently asked questions

   1.   What is work?

    Ans.- Work done is defined as the product of force and mass.

    

   2.   Why does the box move when two persons pushed it in the same direction?

Ans – In this case, the magnitude of the force on the box becomes double so it moves.

   3.   When a man pushes a wall and fails to displace it, what type of work is done in this case?

Ans – In this case, he is not able to displace the wall and no displacement occurs so no work has been done.

 

   4.   When the box is pushed by two persons in opposite directions, the box does not move, why?

Ans - When two persons apply a force of similar magnitude on the box in opposite directions, the resultant force becomes zero, so the box doesn’t move.

 

   5.   What is the S.I. unit of ‘work’?

     Ans-  Joule

Related Topics

1. Activity 11.1

2. Activity 11.3