The letter D represents the wavelength
Answers:
a) 
b) 
c) 
Explanation:
<h3>a) Impulse delivered to the ball</h3>
According to the Impulse-Momentum theorem we have the following:
(1)
Where:
is the impulse
is the change in momentum
is the final momentum of the ball with mass
and final velocity (to the right) 
is the initial momentum of the ball with initial velocity (to the left) 
So:
(2)
(3)
(4)
(5)
<h3>b) Time </h3>
This time can be calculated by the following equations, taking into account the ball undergoes a maximum compression of approximately
:
(6)
(7)
Where:
is the acceleration
is the length the ball was compressed
is the time
Finding
from (7):
(8)
(9)
(10)
Substituting (10) in (6):
(11)
Finding
:
(12)
<h3>c) Force applied to the ball by the bat </h3>
According to Newton's second law of motion, the force
is proportional to the variation of momentum
in time
:
(13)
(14)
Finally:

Answer:
568.18 N
Explanation:
From the question,
The formula for gravitational potential is given as
Ep = mgh........................ Equation 1
Where Ep = Gravitational potential, m = mass of the diver,h = Height.
But,
W = mg.................... Equation 2
Where W = weight of the diver.
Substitute equation 2 into equation 1
Ep = Wh
Make W the subject of the equation
W = Ep/h................... Equation 3
Given: Ep = 25000 J, h = 44 m
Substitute into equation 3
W = 25000/44
W = 568.18 N.
Hence the weight of the diver = 568.18 N
Answer:
Derived in explanation
Explanation:
The law of universal gravitation was discovered by Newton in 1686. According to this law:
“Every object in this universe attracts other body with a force, which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.”
Consider two bodies ‘A’ and ‘B’ having masses ‘m1’ and ‘m2’, respectively. They are placed with their centers at distance ‘r’ from each other.
According to this law, force is directly proportional to the product of their masses, that is:

Also, the force is inversely proportional to the square of the distance between them, that is:

On combining both equations we get:
Where ‘G’ is called ‘Gravitational Constant’ and its value is 6.67 x 10⁻¹¹ Nm²/kg².