# How to find the average speed

The average speed can be calculated by dividing the length of the path traveled by the body in the time spent on it. But in practice, when solving physical problems it is important to keep in mind and some specific nuances.

## Instruction how to find the average speed

Step 1:

Calculate the average velocity of a body moving uniformly throughout the stretch of track. This speed is calculated only simpler because it does not change throughout the movement, and the interval is equal to the average velocity. You can write this as a formula: = Vrd Vav, where Vrd - the speed of uniform motion, and Vav - average speed.

Step 2:

Calculate the average speed ravnozamedlennogo (uniformly accelerated) movement at the site, which must be added to the start and end speed. Halve the result, which will be the average speed. You can write this more clearly as a formula: Vav = (Vr + Vc) / 2, where Vr is the initial velocity, and VR - end.

Step 3:

Take advantage of a special variant of the above formula, if we know the magnitude of the acceleration and initial speed, but not the final velocity is given. Designate acceleration as the ratio "a" and get the formula: VR = a * t + VH. Hence: Vav = (Vc + Vr) / 2 = (a * t + Vr + Vn) / 2 = a * t / 2 + Vr.

Step 4:

Convert the above formula, if the initial velocity is unknown, but given the acceleration and final velocity: Vav = (Vr + Vc) / 2 = (VR + VR - a * t) / 2 = Vc - a * t / 2.

Step 5:

Calculate the average speed if the distance traveled given length (S) and elapsed time of its passage (t), dividing them. To do this use the classic formula: Vav = S / t. Remember that you need to take full account of the time, even if the object is stopped during the passage of the site.