Q.14. Explain these statements
a. Why people sitting in bus fall backward when bus suddenly starts?
b. When a hanging carpet is beaten with stick, the dust particle start coming out of it?
c. When the mango tree is shake, the mangoes are detached from the tree.
d. An athlete always runs some distance before taking a jump.
Answers
Answer:
a) due to acceleration
1. When the bus starts suddenly, then, the lower part of body starts being in motion because it is in touch of bus in motion, while the upper part of body tries to be at rest for sometime, because of inertia at rest. this is why, passengers tends to fall backwardswhen it starts suddenly.
2.When a carpet is beaten with a stick, the dust particles come out. This is because when the carpet is beaten, itcomes in motion but the dust particlestry to remain in rest due to inertia of rest and hence they comes out ofcarpet.
3.When we shake a mango tree, the mangoes fall down. It is because when we shake the tree, the mangoes tend to be at rest due to inertia whereas the branches are in motion. That is why the mangoes get detached from the branches.
4.An athlete runs before jumping to gain momentum. Because it helps in jumping higher and longer because of inertia of motion gained due to the motion. When the athletes Jump they already have a forward motion that would be greater than that of a jump made from standing in one spot.