Question

Calculate the force required to accelerate a car from rest to a velocity of $30m{s}^{-1}$ in $10$ seconds. The mass of the car is $1500kg$.

• A. $4000N$
• B. $3500N$
• C. $3000N$
• D. $4500N$

Answer 1

The correct option is D

$4500N$

Here, mass of car $m=1500kg$, initial velocity $u=0$, final velocity $v=30m{s}^{-1}$, time taken $t=10s$
Let ${}^{\prime }{a}^{\prime }$ be the acceleration.
Now, putting these values in the first equation of motion,
$v=u+at$
we get, $30=0+a\times t$

$\Rightarrow$ $10a=30$

$\Rightarrow$ $a=3m{s}^{-2}$

Now, in equation : F = $m\times a$ putting $m=1500kg$ and $a=3m{s}^{-2}$
we get,
$F=1500\times 3=4500N$. Thus, force required is $4500N$.