Question

Ques 3
A care travels from stop A to stof B with a
speed of 30km/h and then return back to
A with a speed of to A with a speed of 50 km/h. Find: distance travel by the car​

Answer 1

$\sf\star\bold\red{\underline{{QUESTION:-}}}$

✓✓A car travels from stop A to B with a speed of 30km/h and returns back to A with a speed of 50km/hr. Find displacement and distance travelled by the car. what is the average speed of the car

$\sf\star\bold\green{\underline{{SOLUTION:-}}}$

Let the distance from A to B be x.

Then displacement of the car when it comes back to the same position is zero.

But the distance travelled is 2x.

Time taken by the car when it moves from A to B is given by

$\sf\implies\:t1\:=\dfrac{Distance}{Speed}$

$\sf\implies\:t1=\dfrac{x}{30}$

Time taken by the car when it moves from B to A,

$\sf\implies\:t2=\dfrac{Distance}{Speed}$

$\sf\implies\:t2=\dfrac{x}{50}$

$\sf\:Total\:distance\:=\:2x$

$\sf\:Total\:time\:=\:t1 + t2$

$\sf\implies\dfrac{x}{30} +\dfrac{x}{50}$

$\sf\implies\dfrac{(5x + 3x)}{150}$

$\sf\implies\dfrac{8x}{150}$

So,

$\sf\:Average\:speed = \dfrac{Total\:distance}{Total\:time}$

$\sf\implies\:2x\times\:\dfrac{150}{8x}$

$\sf\pink{{\implies\: 37.5 km/hr}}$