Question

A sports car must achieve a velocity of 100m/s after passing the entry tollgate of an expressway. If it can do this after traveling 1km, what must it's acceleration ve?

Answer 1

$v_0=0$

$s _1= 1km=1000\frac{m}{s}$

$v_1= 100\frac{m}{s}$

$v_1 = v_0+at=at$

$at = 100$

$s = v_0t+\frac{at^2}{2}$

$s_1=\frac{at^2}{2}= at*\frac{t}{2}=50t$

$t = 20s$

$a = \frac{v_1}{t}=\frac{100}{20}=5\frac{m}{s^2}$

$\text{Answer: }5\frac{m}{s^2}$