Question

Statement I :A small block of mass m is projected with some speed from point A on a smooth vertical tube track of small diameter as shown in Fig. 8.210. The vertical heights of points B and C from point of projection are $h_{B}and{h}_C$ such that $h_B=2h$ and $h_C=h.$ Then the minimum possible speed of the block at point C is $\sqrt{2gh}$ (where g is acceleration due to gravity).

Statement II . The minimum speed of the block at point C in situation given in Statement I depends on $h_B-h_C.$

• A. Statement I is true, Statement II is true; Statement II is a correct explanation for Statement I.
• B. Statement I is true, Statement II is true; Statement II is not a correct explanation for Statement I.
• C. Statement I is true, Statement II is false
• D. Statement I is false, Statement II is true

Answer 1

The correct option is A Statement I is true, Statement II is true; Statement II is a correct explanation for Statement I.

For speed to be minimum at C, the speed at B should be just zero.