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Question
Two masses of 5 kg and 3 kg are suspended with help of massless inextensible strings as shown in figure. Calculate T1 and T2 when whole system is going upwards with acceleration = 2 ms2 (use g = 9.8 ms–2).
Solution
Given, m1 = 5 kg, m2 = 3 kg
g = 9.8 m/s2 and a = 2 m/s2
For the upper block
T1 – T2 – 5g = 5a
⇒ T1 – T2 = 5(g + a) .....(i)
For the lower block
T2 – 3g = 3a
⇒ T2 = 3(g + a)
= 3(9.8 + 2)
= 35.4 N
From equation (i)
T1 = T2 + 5(g + a)
= 35.4 + 5(9.8 + 2)
= 94.4 N
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