Answer:
Explanation:
The speed of sound in air to be 343 m/s.
Given:
distance 'd' = 5 m
L = 12 m
It can be concluded that path difference must be equal to half of the wavelength when person is observing destructive interference'y' at 1 m distance from the equidistant position
Since
λ/2 = yd/L
λ/2 = (1 x 5)/12
λ = 0.833m
Frequency of the sound is given by,
f = v / λ => 343 / 0.833
f=411.6 Hz
Answer:
Power = 130 watt
Explanation:
Power is described as the ability to do work, it is also defined as the amount of work in Joules done in a given time in seconds. Mathematically, it is represented as:

In this example, power is calculated as follows:
Work = 39000 J
Time = 5 minutes
converting the time from minutes to seconds:
1 minute = 60 seconds
∴ 5 minutes = 60 × 5 = 300 seconds

N:B the unit for power can also be represented as Joules/seconds or J/s or JS⁻¹
Answer:
The distance between the ships changing at 6PM is 21.29Km/h
Explanation:
Ship A is sailing east at 35Km/h and ship B is sailing West at 25Km/h
Given
dx/dt= 35
dy/dt= 25
dv/dt= ???? at t= 6PM - 2PM= 4
Therefore t=4
We know ship A travels at 150km in the x-direction and Ship A at t=4 travels at 4.35 Which is 140 also in x-direction
So, we use:
;

But ship B travels at t=4, at 4.25 =100 in the y-direction
so, let's use the equation:


Lets use 2DD' = 2xx' + 2yy'
Differentiating with respect to t we have:
D•d(D)/dt = -(10)•dx/dt + 100•dy/dt
=100.5 d(D)/dt = (-10)•35 + (100)•25
When t=4, we have x=(140-150) =10 and y=100

=100.5
= 100.5 dD/dt = 10.35 +100.25
= dD/dt = 21.29km/h
Answer:
It is called an organ System
Present day earth is in the Cenozoic era and the time period for it is 66 million years ago to today.