Answer:
a) 


b) 

c)

Explanation:
We have:
m: is the ball's mass = 1.5 kg
v₀: is the initial speed = 15 m/s
g: is the gravity acceleration = 9.81 m/s²
a) In the initial position we have:
h: is the height = 0
The potential energy is given by:

The kinetic energy is:

And the mechanical energies:

b) At 5 m above the initial position we have:
h = 5 m
The potential energy is:

Now, to find the kinetic energy we need to calculate the speed at 5 m:



And the mechanical energies:
c) At its maximum height:
: is the final speed = 0

Now, the potential, kinetic and mechanical energies are:

I hope it helps you!
So the answer is B) he should wire each room in parallel. This is because when the bulbs are in parallel if one part of the parallel circuit is broken (eg when you switch a light off) then the current can still flow to all the other bulbs, meaning they stay turned on. Hope this helps :)
No becuase the simplified case of constant speed, use the formula:
<span>distance = speed x time</span>
Explanation:
It is given that,
Mass of the ball, m = 0.06 kg
Initial speed of the ball, u = 50.4 m/s
Final speed of the ball, v = -37 m/s (As it returns)
(a) Let J is the magnitude of the impulse delivered to the ball by the racket. It can be calculated as the change in momentum as :

J = -5.24 kg-m/s
(b) Let W is the work done by the racket on the ball. It can be calculated as the change in kinetic energy of the object.


W = -35.1348 Joules
Hence, this is the required solution.