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Question
In the previous problem, suppose m2 = 2.0 kg and m3 = 3.0 kg. What should be the mass m, so that it remains at rest?
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Solution
For m1 to be at rest, a1 = 0.
T − m1g = 0
T = m1g ...(i)
For mass m2,
T/2 − 2g = 2a
T = 4a + 4g ...(ii)
For mass m3,
3g – T/2= 2a
T = 6g − 6a ...(ii)
From equations (ii) and (iii), we get:
3T – 12g = 12g – 2T
T = 24g/5= 4.08g
Putting the value of T in equation (i), we get:
m1 = 4.8kg
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