Question

An object starts from rest attaining the speed of 50m/s after travelling a

distance of 400m. Find the acceleration of the object​

Answer 1

Acceleration - Motion

As per the question, the object starts from rest and it is attaining the speed of 50m/s. After that, the car is travelling a distance of 400m.

But according to the given information, the object starts from from rest, i.e, the initial velocity of the object will be 0, although the final velocity will have some value.

Here, we concluded that:

$\implies \: u_{object} = 0 \: ms^{-1}$

Simply applying the third equation of motion we can get the acceleration of the object. Third equation of motion deals with the final velocity, initial velocity, acceleration and distance travelled by the object respectively.

In mathematical term it would be like this;

$\implies\: v^2 = u^2 + 2as$

Now simply applying the equation of kinematics :

$\implies \: (50)^{2} = {(0)}^{2} + 2 \times a \times 400 \\ \\ \implies \: 2500= {(0)}^{2} + 2 \times a \times 400 \\ \\ \implies \: 2500 = 0 + 2 \times a \times 400 \\ \\ \implies \:2500 = 0 + 800 \times a \\ \\ \implies \:2500 = 0 + 800a \\ \\ \implies \:2500 = 800a \\ \\ \implies \:a = \cancel\frac{2500}{800} \\ \\ \implies \: \boxed{ \bf{a = 3.12 \: ms^{ - 2} }}$

So our final answer is :

Acceleration of the object is 3.12 m/s².

Answer 2

Given :-

An object starts from rest attaining the speed of 50m/s after travelling a  

distance of 400m

To Find :-

Acceleration

Solution :-

We know that

v² - u² = 2as (3rd equation of motion)

Where

v = final velocity

u = initial velocity

a = acceleration

s = distance

(50)² - (0)² = 2a(400)

(50 × 50) - (0 × 0) = 800a

2500 - 0 = 800a

2500 = 800a

2500/800 = a

25/8 = a

3.125 = a

Hence

Acceleration is 3.125 m/s²

[tex][/tex]