Describe each effect of the force given below with one example.
(i) Make an object move from rest.
(ii) May change the speed of an object.
(iii) May bring about a change in the shape of an object Ans.

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(a)

In walking the pressure on the ground is more as compared to that in standing on the ground. Explain this statement.

5

(a)

Briefly explain the concept of variation of atmospheric pressure.

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(a)

Two women are of the same weight. One wears sandals with pointed heels while the other wears sandals with flat sales. Which one would feel more comfortable while walking on a sandy beach? Give reasons for your answer .

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(a)

Observe the vessels A, B, C and D as shown in figure carefully.

Volume of water taken in each vessel is as shown. Arrange them in the order of decreasing pressure at the base of each vessel. Explain.

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(a)

It is difficult to cut cloth using a pair of scissors with blunt blades. Explain.

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(a)

Mention the name of the type of forces involved in the situations given below.
(a) A horse pulling a cart.
(b) A sticker attached to steel almirah without glue.
(c) A coin falling to the ground on slipping from hand.
(d) A plastic comb rubbed in dry hair picking up tiny pieces of papers.
(e) A moving boat coming to rest when rowing is stopped.

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(a)

Amit and Sumit were good friends. They both went to gym center for exercise. As, the coach of gym told them to complete 10 dips each. So, Amit started doing it by stretching the palms on the floor while Sumit opted to do the same job on pair of rods at some height from floor.
(a) Amit got less pain while Sumit got more pain on his palm. Why?
(b) Mention the idea used by Amit here.

5

(a)

Experimentally explain that pressure is exerted by liquids and gases on the walls of the containers.

5

(a)

What are contact and non-contact forces? Explain briefly with suitable examples.

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(a)