Question

A motorcycle travels 36metre in 3 seconds. What is its speed?

a. 12m/s b. 108 m/s c. 39 m/s​

Answer 1

$\pink\checkmark\:\:{\underline{\red{\boxed{\bf{Correct\:Option\:\longrightarrow\:{\purple{(a)\:12\:m/s}}}}}}}$

$\\ \Large{\bf{\underline{\green{GiVeN\::}}}}$

• A motorcycle travels 36 m in 3 seconds.

$\longmapsto\:\:\bf\blue{Distance\:=\:36\:m}$

$\longmapsto\:\:\bf\orange{Time\:=\:3\:s}$

$\\ \Large{\bf{\underline{\pink{To\:Find\::}}}}$

• The speed of the motorcycle.

$\\ \Large{\bf{\underline{\purple{CaLcUlAtIoN\::}}}}$

$\bf\red{We\:know\:that,}$

$\pink\bigstar\:\:{\underline{\blue{\boxed{\bf{\green{Speed\:=\:\dfrac{Distance}{Time}\:}}}}}}$

$:\implies\:\:\bf{Speed\:=\:\dfrac{36}{3}\:}$

$:\implies\:\:\bf\orange{Speed\:=\:12\:m/s}$

$\\ \Large\bf\blue{Therefore,}$

a) The speed of the motorcycle is 12 m/s.

Answer 2

Given :

• Distance travelled by motorcycle, D = 36 m
• Time interval , t= 3 sec

To Find :

Speed of the motorcycle

Theory :

• Speed :

The rate of change of position of the object in any direction.

${\blue{\boxed{\large{\bold{Speed=\frac{Distance\:Travelled}{Time\:interval}}}}}}$

In differential form:

$\sf\:Speed,V=\dfrac{dx}{dt}$

Solution :

We have , to find the speed of the motorcycle.

Distance traveled , S = 36 m

Time taken , t = 3 sec

Thus ,

$\sf\green{Speed=\dfrac{Distance}{Time\:interval}}$

$\sf\implies\:v=\dfrac{36}{3}$

$\sf\implies\:v=12$

$\sf\implies\:v=12ms^{-1}$

Therefore , Correct option is a)

___________

More information about topic.

• Speed is a scalar quantity.
• It gives no information about the direction of motion of the object .
• It can be zero , postive but never be negative .
• Dimension of Speed: $\sf\:[M^0LT{}^{-1}]$
• SI unit is m/s
• CGS unit is cm/s