A car takes 30 m to stop on wet pavement. How fast was it travelling?

To find out the speed at which the car was travelling, we need to use the formula:

v = √(2ad)

Where:
v is the initial velocity (speed) of the car
a is the acceleration (which in this case is deceleration) of the car
d is the distance the car took to stop

In this case, the car stops, so its final velocity is 0 m/s (since it has come to a halt). The initial velocity will be positive since the car was moving. Therefore, we can rewrite the formula as:

0 = √(2a * 30)

To solve for a, we need to rearrange the equation:

0 = √(2a * 30)
0 = √(60a)

Now, we square both sides of the equation to eliminate the square root:

0^2 = (√(60a))^2
0 = 60a

From this equation, we can see that a (acceleration) is equal to 0. Therefore, the car was traveling at a constant speed and did not decelerate.

Since it takes 30 meters to stop, the car was traveling at a constant speed of any value before coming to a stop.

no idea. How long did it take?

s = 1/2 at^2

All we have is the distance s.