Two tennis balls of mass 60gm are attached with a massless

Last updated: 6/25/2023

Two tennis balls of mass 60gm are attached with a massless rubber thread and held in the vertical position as shown in the figure In this position length of the rubber thread is 40cm and it is unstretched The upper ball is showly raised vertically upward until the lower ball just becomes unsupported by the ground At this time the length of the thread is 1m The rubber thread exerts and force which is proportional to its extension What is the force constant of the rubber thread A 2N m B IN m C 0 5 N m How much work is done by external agent while the upper ball was raised A 0 54 J B 0 36 J C 0 18J D 0 25 N m D 0 45 J If we release the upper ball at this position at what speed will it hit the lower one A 4m s B 18 m s C 30 m s D 26 m s