Question

223] A body moves with a uniform acceleration of 2 mls? If its initial
velocity is 10 m's, after how many seconds, will its velocity be 40 mls.​

Answer 1

AnswEr :

As per the provided information in the given question, it has been stated that a body is moving with velocity of 10 m/s and its acceleration is 2 m/s². We have been asked to calculate the time after its velocity will become 40 m/s.

We have,

• Initial velocity (u) = 10 m/s
• Acceleration (a) = 2 m/s²
• Final velocity (v) = 40 m/s

➝ Time taken (t) = ?

Here, we need to apply any of the equations of motion to calculate the time taken.Ther are mainly three equations of motion :

$\boxed{ \begin{array}{cc} \pmb{\sf{ \quad \: v = u + at \quad}} \\ \\ \pmb{\sf{ \quad \: s= ut + \cfrac{1}{2}a{t}^{2} \quad \: } } \\ \\ \pmb{\sf{ \quad \: {v}^{2} - {u}^{2} = 2as \quad \:}}\end{array}}$

We have u , v and a . So, by using the first equation of motion, we can easily find the time taken.

By using the first equation of motion,

$\longrightarrow \boxed{\tt { v = u + at} }$

• v denotes final velocity
• u denotes initial velocity
• a denotes acceleration
• t denotes time

$\longrightarrow \tt { 40 = 10 + 2t}\\ \\ \longrightarrow \tt { 40 - 10 = 2t} \\ \\\longrightarrow \tt { 30 = 2t} \\ \\ \longrightarrow \tt { \cancel{\dfrac{30}{2}} = t} \\ \\ \longrightarrow \underline{\boxed{\tt { 15 = t }}} \; \red{\bigstar}$

Therefore, after 15 seconds, its velocity will become 40 m/s.