Answer:
I really don't know but please if you find the correct answer tell me because I'm eager to know
Answer: The frequency heard will be f = 275.675Hz
Explanation: When an object emitting sound is moving, it occurs a phenomenon called Doppler shift or Doppler effect. What happens is that the sound gets higher when the moving object comes closer the observer and becomes lower after it passes, This change is due to the quantity of waves that passes through an area in an unit of time.
The formula to calculate the Doppler effect is as follows
f = (
) · f₀
f is the observed frequency;
c is the speed of sound;
Vs is velocity of the source;
f₀ is the emitted frequency of source;
Substituting and calculating,
f = 
· 300
f = 275.675 Hz
Thus, the frequency heard by the police officer is 275.675Hz.
Answer:
174.85 W
Explanation:
Area of plate = 3.14 x (15x 10⁻²)²
= 706.5 x 10⁻⁴ m²
heat being radiated by convection = 12 x 706.5 x 10⁻⁴ ( 180 - 15 )
= 139.88 W. This energy needs to be fed by heat source to maintain a constant temperature of 180 degree.
If power of electric source is P
P x .8 = 139.88
P = 139.88 / .8
= 174.85 W
Answer:
Yes
Explanation:
The speed of light when it travels through glass, diamond, etc, the light travels at different speed from the speed of light. Speed of the light in material is related to the index of refraction.
The change in speed which occurs when the light passes from one medium to the another is responsible for bending of the light which is called as refraction.
<u>When the light goes into a medium with the higher index of the refraction, light bends towards normal. Conversely, if the light traveling goes from higher refractive index to lower refractive index, it will bend away from the normal.
</u>
<u>Hence, the refraction is different in both the scenario.</u>
