Question

A car skids to a stop at a stop light 55 meters away. Assuming uniform acceleration of -4.35 m/s?, determine the speed of the car before it began to skid?

Answer 1

The initial speed of the car before it began to skid was 34.7 m/s, calculated using the kinematic equation for motion with a given deceleration and stopping distance.

Step-by-step explanation:

To determine the speed of the car before it began to skid, we can use the kinematic equation which relates initial velocity, final velocity, acceleration, and displacement:

v2 = u2 + 2as

Here, v is the final velocity, u is the initial velocity, a is the acceleration, and s is the displacement. Since the car comes to a stop, v is 0 m/s, a is -4.35 m/s2 (negative because it's deceleration), and s is 55 meters.

Plug the values into the equation:

0 = u2 + 2(-4.35)(55)
Solve for u:

u2 = -2(-4.35)(55)
u2 = 2(4.35)(55)
u = √[2(4.35)(55)]
u = 34.7 m/s
The initial speed of the car before it began to skid was 34.7 m/s.