1. Tardigrade
  2. Question
  3. Physics
  4. The acceleration ‘a’ (in ms-2)of a body, starting from rest varies with time t (in s) following the equation a = 3t + 4 The velocity of the body at time t = 2s will be

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. The acceleration ‘a’ $\left(in \,ms^{-2}\right)$of a body, starting from rest varies with time $t$ (in $s$) following the equation $a = 3t + 4$ The velocity of the body at time $t = 2s$ will be

WBJEEWBJEE 2009Motion in a Straight Line

Solution:

Given $a=3 t+4$
$\Rightarrow \frac{d v}{d t}=3 t+4$
$\therefore \int\limits_{0}^{v} d v=\int\limits_{0}^{t}(3 t+4) d t$
$\Rightarrow v=\frac{3}{2} t^{2}+4 t$
at $t=2 s$
$v =\frac{3}{2}(2)62 + 4(2)$
$ = 14\,ms^{-1}$