Hey guys can you help me solve this problem "how long will it take a car travelling 30m/s to come to stop ifs its acceleration is -3 m/s2".

10 seconds.

Explanation:

We can use a kinematic equation where we know the final velocity, initial velocity, acceleration, and need to determine the time t:

The initial velocit is 30 m/s, the final velocity is 0 m/s (as we stopped), and the acceleration is -3 m/s².

Substitute and solve for t:

Hence, it will take the car 10 seconds to come to a stop.

does anyone know or what?

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.