Q29 of 82 Page 79

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?



Given: m1= 1kg, m2= 2kg, m3=3kg


For m1 to be at rest, a1 = 0.


T − m1 g = 0


T = m 1g …(i)


For mass m2, − 2g = 2a


T = 4a + 4g …(ii)


For mass m3, 3g – = 2a


T = 6g − 6a


From equations (ii) and (iii), we get:


3T – 12g = 12g – 2T


T = = 4.08g


Substitute the value of T in equation (i), we get: m1 = 4.8kg


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