Answer:
Explanation:
The definition of the intensity in terms of power is given by:
Where:
- P is the power
- A is the area
If the sound emits uniformly in all directions and that there are no reflections, we can assume the geometry of the wave sound is spherical.
Let's recall the area of a sphere is 
To the first location we have:
and to the second location we have:
Now, we can divide each intensity to find the second intensity.
I hope it helps you!
Answer:
The gazelles top speed is 27.3 m/s.
Explanation:
Given that,
Acceleration = 4.2 m/s²
Time = 6.5 s
Suppose we need to find the gazelles top speed
The speed is equal to the product of acceleration and time.
We need to calculate the gazelles top speed
Using formula of speed
Where, v = speed
a = acceleration
t = time
Put the value into the formula
Hence, The gazelles top speed is 27.3 m/s.
Answer: V = 15 m/s
Explanation:
As stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. The observed frequency the car will be experiencing will be addition of the two frequency. That is,
F = 2.1 × 10^10 + 1030 = 2.100000103×10^10Hz
Using doppler effect formula
F = C/ ( C - V) × f
Where
F = observed frequency
f = source frequency
C = speed of light = 3×10^8
V = speed of the car
Substitute all the parameters into the formula
2.100000103×10^10 = 3×10^8/(3×10^8 -V) × 2.1×10^10
2.100000103×10^10/2.1×10^10 = 3×108/(3×10^8 - V)
1.000000049 = 3×10^8/(3×10^8 - V)
Cross multiply
300000014.7 - 1.000000049V = 3×10^8
Collect the like terms
1.000000049V = 14.71429
Make V the subject of formula
V = 14.71429/1.000000049
V = 14.7 m/s
The speed of the car is 15 m/s approximately
Answer:
true
Explanation:
if there is no light it's different from when there is
Answer:
some symptoms can be lack of energy, and dizziness.
Explanation:
