Activity 9.4 Class 9 Science Force and Laws of Motion Chapter 9
Activity 9.4 asks us to stand on a cart and play the game of catching sandbags.
Observation:
While throwing the bag our body and the bag also moves but in the opposite direction of the bag.
Explanation:
For every reaction, there is an equal and opposite reaction. Here when we throw the bag, it exerts an opposite force on the body. As a result, the cart also starts moving but in the opposite direction. It was Newton, who first saw this effect. So, we call this as Newton’s third law of motion.
Inference:
For every action, there is an equal and opposite reaction.
Similar examples:
Recoiling of a gun after firing: You must have seen a jerking effect of a gun while firing. When bullet moves ahead it exerts an opposite and equal force on the gun. As a result, the gun recoils with great force as well. To overcome this effect, the gun is made heavy with a big base.
Force = m1a1 = m2a2
m1↓a1↑ = m2↑a2↓
Next: Activity 9.5 Class 9 Science Force and Laws of Motion.
See also: Activity 9.3 Class 9 Science Force and Laws of Motion.
Activity 9.4 Class 9 Science Force and Laws of Motion
Ref: Class 9 Science chapter 9.
