A particle moves for $8\, seconds$. It first accelerates from rest and then retards to rest. If the retardation be $3\, times$ the acceleration, then time for which it accelerates will be
$2 $
$3$
$4$
$6$
From the $v-t$ graph, the
A bullet moving with a velocity of $100\, m/s$ can just penetrate two planks of equal thickness. The number of such planks penetrated by the same bullet, when the velocity is doubled, will be
Velocity of a particle is in negative direction with constant acceleration in positive direction. Then, match the following columns.
Colum $I$ | Colum $II$ |
$(A)$ Velocity-time graph | $(p)$ Slope $\rightarrow$ negative |
$(B)$ Acceleration-time graph | $(q)$ Slope $\rightarrow$ positive |
$(C)$ Displacement-time graph | $(r)$ Slope $\rightarrow$ zero |
$(s)$ $\mid$ Slope $\mid \rightarrow$ increasing | |
$(t)$ $\mid$ Slope $\mid$ $\rightarrow$ decreasing | |
$(u)$ |Slope| $\rightarrow$ constant |
A car, moving with a speed of $50 \,km/hr$, can be stopped by brakes after at least $6\,m$. If the same car is moving at a speed of $100 \,km/hr$, the minimum stopping distance is..........$m$
If a body starts from rest and travels $120 \,cm$ in the $6^{th}$ second, then what is the acceleration.........$m/{s^2}$