Answer:
The initial velocity of the ball is <u>39.2 m/s in the upward direction.</u>
Explanation:
Given:
Upward direction is positive. So, downward direction is negative.
Tota time the ball remains in air (t) = 8.0 s
Net displacement of the ball (S) = Final position - Initial position = 0 m
Acceleration of the ball is due to gravity. So,
(Acting down)
Now, let the initial velocity be 'u' m/s.
From Newton's equation of motion, we have:

Plug in the given values and solve for 'u'. This gives,

Therefore, the initial velocity of the ball is 39.2 m/s in the upward direction.
Answer:
S = 16 m
Explanation:
Given that
The frequency of the water waves, f = 4 Hz
The wavelength of the water waves, λ = 2 m
The time the waves reached the shore, t = 2 s
The relation between the velocity, wavelength, and the frequency of the wave is given by the relation,
v = f λ m/s
Substituting the given values in the above equation,
v = 4 x 2
= 8 m/s
The velocity of the water waves is v = 8 m/s
The distance between the shore and boat is given by
s = v x t
= 8 x 2
= 16 m
Hence, the distance between the boat and the shore is, s = 16 m
I = E / R
If the resistors are in series, the current is 0.3 Amperes.
If the resistors are in parallel, the current is 1.25 Amperes.
Gravity is counteracted by centripetal force, due to acceleration, which is the force that pushes you into your seat.