A sailor jumps out from a small boat to the shore (Fig.). Class 9

A sailor jumps out from a small boat to the shore (Fig.). Class 9

Question 1.

A sailor jumps out from a small boat to the shore (Fig.). As the sailor jumps forward will the boat move? If yes, in which direction and why. Class 9

Answer:

Yes, the boat will move. When the sailor jumps forward (towards the shore), by Newton's third law, the sailor's feet apply a force on the boat in the backward direction (away from shore). The boat, being on water with negligible friction, will move backward (away from shore) in response to this equal and opposite reaction force.

Question 2.

During a high jump event, a landing mat or sand bed is placed for the athlete to fall upon (Fig.). Explain the reason behind it. Class 9

Answer:

When the athlete falls onto a soft mat or sand, the time taken for their velocity to reduce to zero is increased (compared to falling on a hard surface). By Newton's second law, for the same change in velocity, a longer time results in a smaller acceleration (deceleration). A smaller acceleration means a smaller force is exerted on the athlete's body. This significantly reduces the risk of injury upon landing.