Question

Two bikes are travelling at 10km/hr and are 5 km away from each other. How long before the hit each other?​

Answer 1

Answer:

15 mins.

Step-by-step explanation:

Two bikes are traveling at a rate of 10 km/h.

There are "two" bikes that are traveling towards each other at a rate of 10 km/h.

This means the distance between them is decreasing at a rate of 20 km/h.

Since, speed is nothing but the distance covered in unit time,

If the distance between them decreases by x kms from one side it also decreases by another x kms from the other side, making it decrease by 2x kms in one unit time.

Because both the bikes are traveling at the same speed towards each other, and covers same distance in unit time.

Therefore, their "Relative speed" is 20 km/ h

since the cause of decrement by 2x is their velocity, one10 km/h causes a decrease of x kms so two 10 km/h will cause a decrease of 2x and two 10 km/h are 20 km/h

and the "Relative distance" remains 5 km

We have:

$\boxed{\mathfrak{Speed =\frac{Distance}{Time} }}$

$\implies \mathsf{20=\frac{5}{time} }$

"time" and "20" can interchange places

$\implies \mathsf{time=\frac{5}{20} }$

$\implies \mathsf{time=\frac{1}{4} \:hrs}$

which is 15 minutes.

So, they hit each other after the time passes by 15 mins.

                             

$\overline{\mathfrak{There\:You\:Are!}}$

[The following attachment will help you visualize better]

Answer 2

Answer:

15 km

Step-by-step explanation:

Hope it's helpful for you