A body is thrown vertically up with a velocity u. It passes three points A, Band e in its upward journey with velocities $\frac{u}{2}, \frac{u}{3} and \frac{u}{4}$ , respectively. The ratio of the separations between points A and B and between B and C, i.e. $\frac{AB}{BC}$ is

see full answer

21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!

An Intiative by Sri Chaitanya

$\frac{10}{7}$

$\frac{20}{7}$

answer is D.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

$A \Rightarrow \frac{u^{2}}{4} - u^{2} = - 2 g h_{1}$

$B \Rightarrow \frac{u^{2}}{9} - u^{2} = - 2 g h_{2}$

$C \Rightarrow \frac{u^{2}}{16} - u^{2} = - 2 g h_{3}$

$∴$ $A B = \frac{u^{2}}{2 g} (\frac{8}{9} - \frac{3}{4}) = \frac{u^{2}}{2 g} \cdot \frac{5}{36}$

$B C = \frac{u^{2}}{2 g} (\frac{15}{16} - \frac{8}{9}) = \frac{u^{2}}{2 g} \cdot \frac{7}{144}$

$∴$ $\frac{A B}{B C} = \frac{5}{36} \times \frac{144}{7} = \frac{20}{7}$

Watch 3-min video & get full concept clarity