Question

In the figure, the wedge is pushed with an acceleration of 10$\sqrt { 3 }$m/s². It is seen that the block starts climbing upon the smooth inclined face of wedge. What will be the time taken by the block to reach the top ?

• A. $\frac { 2 } { \sqrt { 5 } }$ s
• B. $\frac { 1 } { \sqrt { 5 } }$ s
• C. $\sqrt { 5 }$ s
• D. $\frac { \sqrt { 5 } } { 2 }$ s

Answer 1

Answer: (B)

$\frac { 1 } { \sqrt { 5 } }$ s

Answer 2

acceleration of block relative to wedge,

= a cos q – g sin q (up the plane)

= 10 ( $\sqrt { 3 }$ ) $\left( \frac { \sqrt { 3 } } { 2 } \right)$ – 10 $\left( \frac { 1 } { 2 } \right)$

Then l = $\frac { 1 } { 2 }$ a_net t²