Chapter 4 - Force and Motion - Learning Path Questions and Exercises - Exercises - Page 139: 69

$32.8m$

Initial velocity = $50km/hr=13.89m/s$ Also, $S=\frac{v^{2}-u^{2}}{2a}$ $F=-coefficient \,of\, friction\times mg=ma$ $a=-coefficient \,of\, friction\times g=-0.3\times9.8$ So, $S=\frac{13.89^{2}}{2\times0.3\times9.8}=32.8m$