I'm having trouble finding/understanding the answer to this.
"A car of mass 25000 kg traveling at 2.45 m/s experiences a braking force and uniformly comes to a complete stop over a distance of 150m. What is the deceleration experienced by the car?"
I don't know why I'm having trouble with this, or what I'm missing when I try to do this, but if someone could explain it to me, not just give the answer, it would be greatly appreciated.
Thanks!
"A car of mass 25000 kg traveling at 2.45 m/s experiences a braking force and uniformly comes to a complete stop over a distance of 150m. What is the deceleration experienced by the car?"
I don't know why I'm having trouble with this, or what I'm missing when I try to do this, but if someone could explain it to me, not just give the answer, it would be greatly appreciated.
Thanks!
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In this problem the mass of the car is not necessary to solve for the deceleration. We know the initial velocity (Vo = 2.45m/s), the total distance traveled (d = 150m), and the final velocity (V = 0). Since the force acting on the car is constant, and the mass of the car is constant, we can assume that the acceleration (a) is constant. Because the acceleration is in the direction opposite the direction of the velocity, it is given a negative value. We can solve for the deceleration using the equation:
V^2 = Vo^2 + (2 x a x d) Solve for a
V^2 = 0
a = -(Vo)^2 / (2 x d)
a = -(2.45)^2 / (2 x 150m) = 2.00 x 10^-2 m/s^2
V^2 = Vo^2 + (2 x a x d) Solve for a
V^2 = 0
a = -(Vo)^2 / (2 x d)
a = -(2.45)^2 / (2 x 150m) = 2.00 x 10^-2 m/s^2