Question

How long does it take a car to cross a 30 m wide intersection after the light turn green, if

the car accelerates from rest at a constant 3.00 m/s2

Answer 1

`t=4.47s`

Step-by-step explanation:

Hello,

In this case, since the car starts from from rest whereas the initial velocity is zero, we can compute the time via the following equation:

`d=v_0*t+(1)/(2)at^2\\\\d=(1)/(2)at^2`

Which is solving by applying square root:

`3.00t^2=2*30\\\\t=\sqrt{(2*30m)/(3.00m/s^2) }\\ \\t=4.47s`

Best regards.