Atoy car of mass 6 kg, moving in a straight path, experiences a net force given by the function f = −3t. at time t = 0, the car has a velocity of 4 m/s in the positive direction and is located +8 m from the origin.
the car will come instantaneously to rest at time t equal to

The car will come instantaneously to rest at time t equal to 4 seconds.

Explanation:

"The acceleration varies linearly with time

As here the accelartion varies with respect to time so we can not simply apply Newtons Law"

Using the informations:

Area = F*t/2 = -3t²/2

I = Qf - Qi (Qf = 0, the velocity is zero)

So I = -Qi = -mv

I = -6*4 = -24

-24 = -3t²/2

t = 4s

t = 4 s

Explanation:

We all know that:

I = F*dt.

And the impulse is the variation of the linear momentum.( I = dP)

Now,

Area = F*t/2 = -3t²/2

I = Pf - Pi (Pf = 0, the velocity is zero)

So,

I = -Pi = -mv

I = -6*4 = -24

-24 = -3t²/2  

48 = 3t²

16 = t²

t = 4 s

∴ The car will come instantaneously to rest at time t equal to 4 s

the answer is neither ball has a charge.

because if they were both positively charged, they will repel each other.

if they were positively and negatively charged, they will seek.

i just did an experiment like this in my science class. also the answer is yes, it will get separated because they are two opposites meaning if they are opposite they can not attract.

hope this .!