Question

A motorcycle goes from 0 m/s (rest) to 40m/s in 8 seconds. Calculate her acceleration.

Answer 1

Anѕwєr :

$\Huge\boxed{\purple{\sf{ 5 \; m\:s^{-2}}}}$

Explαnαtion :

As per the provided information in the given question, we have :

• Initial velocity, u = 0 m/s [Starts from rest]
• Final velocity, v = 40 m/s
• Time taken, t = 8 seconds

$\longrightarrow$ We've been asked to calculate the "acceleration".

$\mapsto \large {\underline {\purple{ \textbf{\textsf {Acceleration :}}}}}$

• Acceleration is the rate of change in velocity. It is a vector quantity that means it requires both magnitude and direction for its description. Its SI unit is m/s².

As I said, acceleration is the rate of change in velocity, so mathematically :

$\dashrightarrow\sf {Acceleration = \dfrac{Change \; in\; Velocity}{Time} }$

Change in velocity can be calculated by finding the difference of final velocity and initial velocity.

$\dashrightarrow\sf {Acceleration = \dfrac{Final \; Velocity - Initial \; Velocity}{Time} }$

So, basically we can say that :

$\dashrightarrow \boxed{\sf {a = \dfrac{v - u}{t} }}$

Now, substitute the values in the above formula.

$\dashrightarrow \sf {a = \dfrac{40 - 0}{8}\; m \: s^{-2} }$

$\dashrightarrow \sf {a = \cancel{\dfrac{40}{8}}\; m \: s^{-2} }$

$\dashrightarrow\boxed{\purple{\sf{ 5 \; m\:s^{-2} = a}}}$

∴ The acceleration of the motorcycle is 5 m/s².

$\rule{200}2$