Answer:
The velocity of the second car when it passes the first car is 40 m/s
Explanation:
The position and velocity of the cars is given by the following equations:
x = x0 + v0 · t + 1/2 · a · t²
v = v0 + a · t
Where:
x = position at time t
x0 = initial position
v0 = initial velocity
t = time
a = acceleration
v = velocity at time t
If the velocity is constant, then a = 0 and x = x0 + v · t
When the second car passes the first car, the position of both cars is the same:
x first car = x second car
x0 + v · t = x0 + v0 · t + 1/2 · a · t² (x0 = 0 and v0 = 0)
v · t = 1/2 · a · t²
2 · v /a = t
2 · 20 m/s / 2.0 m/s² = t
t = 20 s
Using the equation of velocity, we can calculate the velocity of the second car at t = 20 s
v = v0 + a · t
v = 0 m/s + 2.0 m/s² · 20 s = 40 m/s
The velocity of the second car when it passes the first car is 40 m/s
