Answer:
Explanation:
Intensity of light is inversely proportional to distance from source
I ∝ 1 /r² where I is intensity and r is distance from source . If I₁ and I₂ be intensity at distance r₁ and r₂ .
I₁ /I₂ = r₂² /r₁²
If r₂ = 4r₁ ( given )
I₁ / I₂ = (4r₁ )² / r₁²
= 16 r₁² / r₁²
I₁ / I₂ = 16
I₂ = I₁ / 16
So intensity will become 16 times less bright .
"16 times " is the answer .
Answer:
In a global convection cell less –dense air at the equator rises and flows towards the poles. And from pole, the dense air sinks down and flows back towards the equator.... This movement of air is also supported by the Earth's rotation known as Coriolis Effect.
Answer:
32000 N
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 40 m/s
Distance (s) = 10 m
Final velocity (v) = 0 m/s
Mass (m) of car = 400 Kg
Force (F) =?
Next, we shall determine the acceleration of the the car. This can be obtained as follow:
Initial velocity (u) = 40 m/s
Distance (s) = 10 m
Final velocity (v) = 0 m/s
Acceleration (a) =?
v² = u² + 2as
0² = 40² + (2 × a × 10)
0 = 1600 + 20a
Collect like terms
0 – 1600 = 20a
–1600 = 20a
Divide both side by –1600
a = –1600 / 20
a = –80 m/s²
The negative sign indicate that the car is decelerating i.e coming to rest.
Finally, we shall determine the force needed to stop the car. This can be obtained as follow:
Mass (m) of car = 400 Kg
Acceleration (a) = –80 m/s²
Force (F) =?
F = ma
F = 400 × –80
F = – 32000 N
NOTE: The negative sign indicate that the force is in opposite direction to the motion of the car.
<span>it will be changed by changing the medium of the wave</span>
Explanation:
We need to calculate the speed of light in each materials
(I). Gallium phosphide,
The index of refraction of Gallium phosphide is 3.50
Using formula of speed of light
....(I)
Where,
= index of refraction
c = speed of light
Put the value into the formula
![v=\dfrac{3\times10^{8}}{3.50}](https://tex.z-dn.net/?f=v%3D%5Cdfrac%7B3%5Ctimes10%5E%7B8%7D%7D%7B3.50%7D)
![v=8.6\times10^{7}\ m/s](https://tex.z-dn.net/?f=v%3D8.6%5Ctimes10%5E%7B7%7D%5C%20m%2Fs)
(II) Carbon disulfide,
The index of refraction of Gallium phosphide is 1.63
Put the value in the equation (I)
![v=\dfrac{3\times10^{8}}{1.63}](https://tex.z-dn.net/?f=v%3D%5Cdfrac%7B3%5Ctimes10%5E%7B8%7D%7D%7B1.63%7D)
![v=1.8\times10^{8}\ m/s](https://tex.z-dn.net/?f=v%3D1.8%5Ctimes10%5E%7B8%7D%5C%20m%2Fs)
(III). Benzene,
The index of refraction of Gallium phosphide is 1.50
Put the value in the equation (I)
![v=\dfrac{3\times10^{8}}{1.50}](https://tex.z-dn.net/?f=v%3D%5Cdfrac%7B3%5Ctimes10%5E%7B8%7D%7D%7B1.50%7D)
![v=2\times10^{8}\ m/s](https://tex.z-dn.net/?f=v%3D2%5Ctimes10%5E%7B8%7D%5C%20m%2Fs)
Hence, This is the required solution.