Question

A ball is thrown upward with a such a velocity V then it returns to the thrower after 3 seconds if g is equal to 10 M per second find the value of V

Answer 1

hello...
here is your answer ....

we know the final velocity of the ball will be 0 when it reaches its maximum height so ➡➡➡➡let the final velocity be x = 0 m/s

Now time taken to come down by ball = 3s

Means total time travelled by ball is 3s..

$<b><i><u> And as we know that the time taken by object to go up the same time it takes to reach down </b></i></u>$

So time taken by ball to go up ,t = 3/2➡1.5

Now.
gravity is acting in opposite direction so we will take it as '-' so g ➡ -10 m/s^2

initial velocity (v)= ?
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v=u+gt

x=v+gt
$<b><i><u>put the values </b></i></u>$

0=v+(-10)15/10
0=v-15
v=15 m/s...

So initial velocity of ball = 15 m/s
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hope it helps you

Answer 2

Explanation:

Let the time be t seconds

Final velocity of the ball will be zero as it has reached the maximum height

so v= 0 m/s

Total time = 3 seconds

Time taken to reach the maximum distance =

3/2 = 1.5 seconds

g is negative as it is acting upon opposite direction = - 10 m/s2

Initial Velocity = v= u + gt

0= u + (-10) X 15/10

u= 15m/s