A drag racer starts her car from rest and accelerates at 9.0 m/s2for the entire distance of 105.0 m. What is its speed at the end of the run? Answer in units of m/s.
v = 9.0 t
d = (1/2) a t^2
105 = 4.5 t^2
t = 4.83 seconds
v = 9 * 4.8 = 43.4 m/s
To find the speed of the drag racer at the end of the run, we can use the kinematic equation:
v^2 = u^2 + 2as
Where:
v = final velocity (unknown)
u = initial velocity (0 m/s, since the car starts from rest)
a = acceleration (9.0 m/s^2)
s = distance traveled (105.0 m)
First, we substitute the known values into the equation:
v^2 = 0^2 + 2 * 9.0 * 105.0
Simplifying:
v^2 = 0 + 1890
v^2 = 1890
Taking the square root of both sides to solve for v:
v = √1890
v ≈ 43.5 m/s
Therefore, the speed of the drag racer at the end of the run is approximately 43.5 m/s.