Utilnaro

Mechanics formulas

Speed, distance and time

Calculate average speed, distance travelled, or travel time. The formula can be rearranged for any of the three quantities.

Formula

v=st v = s / t

Average speed equals the distance travelled divided by the elapsed time.

Speed, distance and time calculator

What do you want to calculate?

Known values

The result updates when a value changes.

Result

50 km/h

Substitution and calculation

v = s / t = 100,000 m / 7,200 s = 13.888889 m/s

Unit conversion: 13.888889 m/s = 50 km/h

Symbols and units

SymbolQuantitySISupported units
vaverage speedDistance travelled per unit of time.m/sm/s, km/h, mph
sdistanceThe length of the path travelled during the measured interval.mm, km, cm, mi
telapsed timeThe duration of the measured movement.ss, min, h

Formula rearrangements

Calculate speed

v = s / t

Calculate distance

s = v × t

Calculate time

t = s / v

Worked examples

Average speed of a cyclist

A cyclist travels 36 km in 1.5 hours. Find the average speed.

  1. 1Step 1: Use v = s / t.
  2. 2Step 2: Substitute s = 36 km and t = 1.5 h.
  3. 3Step 3: Divide 36 by 1.5 to obtain 24 km/h.

Result: 24 km/h

Distance travelled by a car

A car maintains 90 km/h for 20 minutes. Find the distance travelled.

  1. 1Step 1: Convert 20 minutes to 1/3 hour.
  2. 2Step 2: Use s = v × t.
  3. 3Step 3: Multiply 90 km/h by 1/3 h to obtain 30 km.

Result: 30 km

Sources and review