A pulley arrangement has 3 movable and 1 fixed pulley. Ideal V.R. is:
A3
B4
C8
D6
Answer & Solution
Correct answer: D. 6
1. Number of strings supporting the movable block equals 2 * (number of movable pulleys).
2. With 3 movable pulleys, supporting strings = 2 * 3 = 6.
3. The fixed pulley does not add to V.R. but only changes direction.
4. Effort end is one of these 6 string ends.
5. So V.R. = 6.
_Source: Selina Concise Physics ICSE Class 10, Ch 3 'Machines' (aplustopper.com extract)_
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