Question

you throw a tennis ball straight upward. the initial speed is about 12 m/s. say everything you can about the motion of the ball. Is 12 m/s realistic speed for an object that you can throw with your hands

Answer 1

The body decelerates upwards at a constant acceleration due to gravity.

The initial speed of the object 12m/s.

The final velocity of the ball is 0.

The ball attains a maximum height.

We can use the kinematics equations such as :

V² = U² - 2gs to get the vertical distance.

The object reaches a maximum height.

From the equation above, we can get the height.

V = 0

U = 12 m/s

Take g = 10

Doing the substitution :

0 =  12² - 10S × 2

144 = 20S

S = 144/20 = 7.2M

And yes the human hand can throw the ball at an initial velocity of 12 m/s.