Important formulae and facts of Time and Distance

1. Formula of Speed

Speed = \begin{aligned} \left(\frac{Distance}{Time} \right) \end{aligned}

So Formula of speed is, speed is equal to distance upon time. If you remember this formula then you will learn next two formulae two.

2. Formula of Time

Time = \begin{aligned} \left(\frac{Distance}{Speed} \right) \end{aligned}

So Formula of time is, time is equal to distance upon speed.

3. Formula of Distance

Distance = (Speed * Time)

So distance is simply speed into time. All three formulae that formula of speed, formula of time and formula of distance are interrelated.

4. Convert from kph(km/h) to mps(m/sec)
For converting kph(kilometre per hour) to mps(meter per second) we use following formula

\begin{aligned}
x&km/hr = \left(x*\frac{5}{18}\right)m/sec
\end{aligned}

6. Convert from mps(m/sec) to kph(km/h)
For converting mps(meter per second) to kph(kilometre per hour) we use following formula

\begin{aligned}
x&m/sec = \left(x*\frac{18}{5}\right)km/h
\end{aligned}


7. If the ratio of the speeds of A and B is a : b, then the ratio of the

the times taken by then to cover the same distance is
\begin{aligned} \frac{1}{a}:\frac{1}{b} & or & b:a \end{aligned}

8. Suppose a man covers a certain distance at x km/hr and an equal distance at y km/hr. Then,

the average speed during the whole journey is
\begin{aligned} \frac{2xy}{x+y} \end{aligned}