Rotational Motion Question 144
Question: Three identical spheres, each of mass 1 kg are , touching each other, with their centres on a straight line. If their centres are marked P, Q, R respectively, the distance of centre of mass of the system from P is
Options:
A) $\frac{PQ+PR+QR}{3}$
B) $\frac{PQ+PR}{3}$
C) $\frac{PQ+QR}{3}$
D) $\frac{PR+QR}{3}$
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Answer:
Correct Answer: B
Solution:
[b]
$x _{cm}=\frac{1\times 0+1\times PQ+1\times PR}{1+1+1}=\frac{PQ+PR}{3}$
$ And $
$y _{cm}=0$
