Question

how to find mean speed​

Answer 1

Answer:

Thus we can find the average speed as: Average Speed = (Total distance)/(Total Time) = (1800 + 1800)/(30 + 45) = 3600/75 = 48 km/hr. Hence the correct option here is C) 48 km/hr. So to find the average speed never use the formula of the averages but try to find the total distance covered and the total time taken.

Answer 2

Answer:

mean speed =

$\sqrt(8rt \div \pi \times m)$

r... gas constant

m... molecular wt of gas

t... temperature if gas