The masses of the bodies A and B in figure are 20 kg and 10 kg, respectively. They are initially at rest on the floor and are connected by a weightless string passing over a weightless and frictionless pulley. An upward force F is applied to the pulley. Find the acceleration a1 of body A and a2 of body B when F is 340 N :
a1 = 7 m/sec², a2 = 24 m/sec²
a1 = 1.5 m/sec², a2 = 7 m/sec²
a1 = 0 m/sec², a2 = 7 m/sec²
Solution:
As F= 340 N. Force acting on object A in upward direction is F/2 i.e 170 N. This force is insufficient to pull the object upwards. (weight of A is greater than 170 N)
So, a1= 0 m/s²
Force acting on B in upward direction is 170 N and weight is 10g or 100 N. Net force in upward direction is 70 N. so,
a2= 7 m/s²
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