A) h=R
B) h = 2R
C) \[h=\frac{5}{2}R\]
D) h = 4R
Correct Answer: C
Solution :
Let v be velocity of the body at C, then \[\frac{m{{v}^{2}}}{R}=mg\] ?.. (i) At A the potential energy is\[mgh\]and at C it is mg (2r). From law of conservation of energy, this loss in potential energy \[mg(h-2R),\]will be equal to kinetic energy of the ball at C, that is \[mg(h-2R)=\frac{1}{2}m{{v}^{2}}\] ...(ii) From Eqs. (i) and (ii), we get \[h=\frac{5}{2}R\]You need to login to perform this action.
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