Question

Hussain is going on his sooty at a speed of $36km/hr$. Then find the how much time will he take to cover $1km$ and $500m$

Answer 1

Hint: We can define the velocity as the distance covered by an object per unit time, Mathematically we can write it as $v=\dfrac{d}{t}$ where $v$ is the velocity and $d$ is the distance covered by the object in time $t$.

Complete step by step answer:
Here we have given the velocity of object and distance covered so from the definition of the velocity we can write time$\left( t \right)$$=\dfrac{d}{v}$ and find the time required by the object to cover the distance $d$ with velocity $v$.
Given that,
Velocity of the scotty is $v=36km/hr$
Here we have to find the time taken by Hussain to cover $1km$ then $d=1km$ and from the expression $v=\dfrac{d}{t}$ we can write
${{t}_{1}}=\dfrac{1km}{36\dfrac{km}{hr}}$
Substituting $1hr=3600\text{ seconds}$ in the above equation, then we have
$\begin{align}
  & {{t}_{1}}=\dfrac{1}{36}\times 3600\text{ seconds} \\
 & {{t}_{1}}=\text{100 seconds} \\
\end{align}$
Hence the time taken for Hussain to cover $1km$ at a speed of $36km/hr$ is $100\text{ seconds}$.
Now we are going to find the time taken by Hussain to cover $500$ meters. So here $d=500m$
${{t}_{2}}=\dfrac{500m}{36\dfrac{km}{hr}}$
Substituting$1$ kilometer is equal to $1000$ meters and $1$ hour is equal to $3600$ seconds, then we have
$\begin{align}
  & {{t}_{2}}=\dfrac{500m}{36\times 1000m}\times 3600\text{ seconds} \\
 & {{t}_{2}}=\text{50 seconds} \\
\end{align}$
Hence the time taken for Hussain to cover $500m$ at a speed of $36km/hr$ is $50$ seconds.
Along the side if you want to calculate the time taken by Hussain to cover $1$ kilometer and $500$ meters then we have to add the time taken by Hussain to cover one kilometer and time taken by Hussain to covet $500$ meters, then we have
$\begin{align}
  & {{t}_{3}}=100\text{ seconds}+50\text{ seconds} \\
 & {{t}_{3}}=150\text{ seconds} \\
\end{align}$

Note:
While dealing with problems having dimensional values, we need to keep an eye on the units of the variables. We can proceed for the calculation whether the all variables are in the same units either they should be in the M.K.S system or C.G.S system. If the variables are not in the same system then we need to convert all the variables into M.K.S or C.G.S systems using unit conversions.