Answer:
W = 907963.50 J = 907.96 J
Explanation:
Note: Refer to the figure attached
Now, from the figure we have similar triangles ΔAOB and ΔCOD
we have
or
Now, the work done to empty the tank can be given as:
or
or
or
or
![W = 6773.76\pi[\frac{5}{3}x^3-\frac{1}{4}x^4]^4_0](https://tex.z-dn.net/?f=W%20%3D%206773.76%5Cpi%5B%5Cfrac%7B5%7D%7B3%7Dx%5E3-%5Cfrac%7B1%7D%7B4%7Dx%5E4%5D%5E4_0%20)
or
![W = 6773.76\pi[\frac{128}{3}]](https://tex.z-dn.net/?f=W%20%3D%206773.76%5Cpi%5B%5Cfrac%7B128%7D%7B3%7D%5D%20)
or
W = 907963.50 J = 907.96 J
This is the Doppler effect.
1. As the sound leaves the horn the sound waves are at first close to each other and as they move outwards they become further apart. The closer the sound waves are the louder the noise.
As the car gets the closer the sound waves get closer, so the horn becomes louder.
2. As the horn moves away, the sound waves become less frequent, causing the pitch to get lower.
Answer:
Explanation:
A thermos helps prevent heat loss when the thermos is holding a hot substance and then helps prevent heat gain when the thermos is holding a cold substance. So a thermos can keep hot things hot and cold things cold.
A light wave that hits the surface of a pool gets refracted and gives us an apparent image of the surface of the pool, following the concepts of refraction.
<u>Explanation:</u>
Let’s recall the concept of refraction when a light wave passes from medium of rarer to denser. There is a change in the speed of light while travelling from medium of rarer to denser.
There can be a change in the direction as well. This property is known as “Refraction” and the best example to see refraction is watching the surface of a clean pond, lake or pool.
When the light travels from a rarer medium (air) to a denser medium (water), it changes its angle of direction and gets refracted and hit to our eye lenses. With this, we see the surface of the pool at a changed angle and it seems to be a bit shallow than its original depth.
Acceleration = change of speed / time = 50/5 = 10m/s^2
