A block of mass 2 kg is hanging over a smooth and light pulley through a light string. The other end of the string is pulled by a constant force F=40N. The kinetic energy of the particle increase 40 J in a given internal of time. Then

A block of mass 2 kg is hanging over a smooth and light pulley through

1.	A block of mass 2 kg is hanging over a smooth and light pulley through a light string. The other end of the string is pulled by a constant force F=40N. The kinetic energy of the particle increase 40 J in a given internal of time. Then
Answer» tensionin the string is 40 N displacementof the block in the given internal of time is 2 m work DONE by gravity is -20J work done by tension is 80 J Solution :`W_("net")=DeltaKE` `(40-20)S=40 rArr S= 2m` Work done by gravity `=(-20)xx2=-40 J` Work done by tension `=40xx2=80 J` `:.` (A, B, D)

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A block of mass 2 kg is hanging over a smooth and light pulley through a light string. The other end of the string is pulled by a constant force F=40N. The kinetic energy of the particle increase 40 J in a given internal of time. Then

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