$Assertion$ : Retardation is directly opposite to the velocity.
$Reason$ : Retardation is equal to the time rate of decrease of speed.
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
If the Assertion is correct but Reason is incorrect.
If both the Assertion and Reason are incorrect.
The position$(x)$ of a particle at any time$(t)$ is given by $x(t) = 4t^3 -3t^2 + 2$ The acceleration and velocity of the particle at any time $t = 2\, sec$ are respectively
The velocity of a body depends on time according to the equation $v = 20 + 0.1{t^2}$. The body is undergoing
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 particle of mass $m$ moves on the x-axis as follows : it starts from rest at $t = 0$ from the point $x = 0$ and comes to rest at $ t= 1$ at the point $x = 1$. No other information is available about its motion at intermediate time $(0 < t < 1)$. If $\alpha $ denotes the instantaneous acceleration of the particle, then