Actually Welcome to the Concept of the Wave Optics.
Whenever the waves are out of phase they form a DESTRUCTIVE interference.
thus,
Destructive Interference occurs when two waves are out of phase.
It looks like a refractor.
Answer:
t = 1,144 s
Explanation:
The simple pendulum consists of an inextensible string with a mass at the tip, the angular velocity of this is
w = √( L / g)
The angular velocity is related to the frequency and period
w = 2π f
f = 1 / T
w = 2π / T
Let's replace
2π / T = √ (L / g)
T = 2π √ (g / L)
Let's calculate
T = 2π √ (9.81 / 18.5)
T = 4,576 s
The definition of period in the time it takes the ball to come and go to a given point (a revolution) in our case we go from the end to the middle point that is a quarter of the path
t = T / 4
t = 4,576 / 4
t = 1,144 s
Answer: 3.49 s
Explanation:
We can solve this problem with the following equation of motion:
(1)
Where:
is the final height of the ball
is the initial height of the ball
is the initial velocity (the ball was dropped)
is the acceleratio due gravity
is the time
Isolating :
(2)
(3)
Finally we find the time the ball is in the air:
(4)
