Question

A body starts from rest and travels for five seconds to make a displacement of 25 m if it has travelled the distance with uniform acceleration a then a is
(a) 3 m/s²
(b) 4 m/s²
(c) 2 m/s²
(d) 1 m/s²

Answer 1

Answer:

The acceleration = $2 m/s^2$ Option c.

Explanation:

If Displacement = s, Initial velocity = u, Acceleration = a, Time = t then

According to the question

s = 25 m, t = 5 sec, u = 0 m/s, a = ?

Straight Line motion with constant acceleration

$s=ut+\frac{1}{2}at^2\\\\\therefore 25=0*5+\frac{1}{2}*a*5^2=\frac{1}{2}*a*25\\\\\implies \frac{1}{2}*a*25=25\\\\\implies a=2m/s^2=Acceleration$

Answer 2

The distance with uniform acceleration a than a is $2\frac{m}{s^{2}} .$

Explanation:

The distance with uniform acceleration then is,

$s=ut+\frac{1}{2} at^{2}$

$25=0*t+\frac{1}{2}a*5*5$

$25=\frac{1}{2a}*25$

$\frac{25}{25}=\frac{1}{2a}$

$\frac{1}{2a} =1$

$1*\frac{2}{1} =a$

$a=2$

Acceleration is $2\frac{m}{s^{2}}$.