How to find time(t) when initial velocity(u),final velocity(v) is given and acceleration(a) is not constant ?

You can do this if you have a working knowledge of calculus.

You need to model the acceleration as a function of time, ie obtain a function a(t) that gives acceleration a for any time t.

Using the fundamental theorem of calculus, you should integrate a(t) from t=0 to a variable value of time t. This should get you an expression in terms of t.

Now set this expression equal to the difference of the final and initial velocity, v-u, and solve for t.

Football was the fourth deadliest sport with a fatality rate of .81 per 100,000 participants. cheerleading, which has been shown to be the most dangerous activity based on injury data, was not included in the study because it was not classified as a sport.this is my answer because it didn’t give me any sports

Hey hope you get the answer but i suck at math sorry : (