Question

13. A car accelerates at a rate of 5 m s-2. Find the increase
in its velocity in 2 s.
Ans. 10 m s-1
​

Answer 1

Here, we are provided in the question that a car accelerates at a rate of 5 m/s². We have find increase in its velocity in 2 s.

Considering the statements given in the question, we have :

• Acceleration (a) = 5 m/s²
• Time (t) = 2 s

We know that,

$\bigstar \: \boxed{\sf {Acceleration = \dfrac{Change\: in \: velocity}{Time} }}$

$\longrightarrow \sf{ 5 m/s^2 = \dfrac{Change\: in \: velocity}{2 \: s} }$

$\longrightarrow$ 5 m/s² × 2 s = Change in velocity

$\longrightarrow \boxed { \sf {10 m/s = Change \: in \: velocity}}$

Therefore, increase in its velocity in 2 s is 10 m/s.

Points to remember :

• Acceleration is defined as rate of change in velocity with time.

• $\boxed{\sf {Acceleration = \dfrac{v -u}{t} }}$

• v denotes final velocity.
• u denotes initial velocity.
• t denotes time.

• SI unit of acceleration is m/s².

• Acceleration is a vector quantity.

• Negative acceleration is called retardation.