_____ is the equation of velocity-time relation.
 

It is known that acceleration,

 $\mathrm{a}$= $\frac{\mathrm{rate} \mathrm{of} \mathrm{change} \mathrm{of} \mathrm{velocity}}{\mathrm{time} \mathrm{interval}}$

$\frac{\mathrm{change} \mathrm{of} \mathrm{velocity}}{\mathrm{time} \mathrm{period}}=\mathrm{final} \mathrm{velocity}- \mathrm{initial} \mathrm{velocity}$

$\mathrm{a}=\frac{\mathrm{v}-\mathrm{u}}{\mathrm{t}}$

$\mathrm{at}=\mathrm{v}-\mathrm{u}$

$\mathrm{v}=\mathrm{u}+\mathrm{at}$

Therefore, the equation of velocity-time is $\mathrm{v}=\mathrm{u}+\mathrm{at}$