The velocity of a ball as it is thrown up is 20 meters/second. it attains zero velocity after 3.5 seconds. what is the average acceleration of the ball during its upward flight?

Explanation:

It is given that, the velocity of a ball as it is thrown up is 20 meters/second. It attains zero velocity after 3.5 seconds.

i.e. The initial velocity of the ball is, u = 20 m/s

Final velocity of the ball is, v =0

Time taken, t =3.5 s

The rate of change of velocity w.r.t time is called the acceleration of the ball.

So,

Hence, the average acceleration of the ball during its upward flight is .

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

answer: strength i guess

explanation: