Answer:
n1 sin θ1 = n2 sin θ2 Snell's Law (θ1 is the angle of incidence)
sin θ2 = n1 / n2 * sin θ1
sin θ2 = 2.4 / 1.33 * sin θ1
sin θ2 = 1.80 * .407 = .734
θ2 = 47.2 deg
<span>Wind is nature's way of balancing the temperature between hot and cold. Wind always flows from heat to cool. When night falls, the air cools. And since it gets cooler at night it reverses.</span>
When a radioactive material is required to be placed in the body, the applications are brachytherapy and radioisotope imaging.
Radioactive materials are elements which has the ability to disintegrate by emitting radioactive substance or radiation. A good example of this is Cobalt-60, Titanium-99 etc.
Brachytherapy is a therapeutic process in which radioactive material is inserted into the body in close proximity to the region affected. The radioactive material emits radiations which are required to control the unwanted biological material in the body. A good application of this is the treatment of cancer using Cobalt-60.
Radioisotope imaging is a diagnostic process which is an imaging technique that may require placing a radioactive material in the body so as to trace or locate the affected part of the body. In this case, the material is used as a tracing element.
The applications that require the placing of radioactive materials in the body are brachytherapy and radioisotope imaging.
For more explanation, visit: brainly.com/question/9790340
The velocity is 6.75
The velocity in the equation stated above can be calculated as follows
m= 2,000
p= 2.25
y= 6000
velocity= 2.25 × 6000/ 2000
= 13500/2000
= 6.75
Hence the velocity is 6.75
Please see the link below for more information.
brainly.com/question/23547288?referrer=searchResults
The Doppler effect is the right concept to solve this problem. The Doppler effect is understood as the change in apparent frequency of a wave produced by the relative movement of the source with respect to its observer. Mathematically it can be described as,

Here,
= Frequency of the sound from the Whistle
f = Frequency of sound heard
v = Speed of the sound in the Air
Replacing we have that





Therefore the minimum speed to know if the whistle is working is 16.33m/s