(i) (a) Define Centre of Gravity,
(b) A hollow icc cream cone has height 6 cm.

1. Where is the position of its centre of gravity from the broad base?
2. Will its position change when it is filled completely with honey? Write Yes or No.

(ii)

Two identical marbles A and B are rolled down along Path 1 and Path 2 respectively.
Path 1 is frictionless and Path 2 is rough.

(a) Which marble will surely reach the next peak?
(b) Along which path/s the mechanical energy will be conserved?
(c) Along which path/s is the law of conservation of energy obeyed?

(iii) Given are two pulleys.

(a) Copy and complete the labelled diagram connecting the two pulleys with a tackle to obtain Velocity Ratio = 2.

(b) If Load=48 kgf and efficiency is 80% then calculate:


1. Mechanical Advantage,
2. Effort needed to lift the load,

Solution

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