Please please help i need to finish this test A ball is thrown vertically upward with an initial velocity of 25 m/s. What is its velocity after 3 seconds in the air? (assume air resistance is negligible)

-4.4 m/s

Explanation:

Since the ball is thrown upward, we can ignore the horizontal velocity. This means that the vertical velocity is 25 m/s. The vertical acceleration is -9.8 m/s^2 (g). This means that after 3 seconds, the velocity would've decreased by 9.8 m/s^2 * 3 s. This is 29.4 m/s.

This should be subtracted from the initial velocity:

25 m/s - 29.4 m/s = -4.4 m/s

Hope this helps!

force is mass*acceleration.

we have a very small mass: 11.4*0.001 kg

if we want 0.035n of force, we need an acceleration:

0.035 = 11.4*0.001*a

a = 0.035/(11.4*0.001) m/s^2