Answer: 15.29
Explanation: there you go have a nice day (*^p^*)
Answer:
it is the physics that explains how everything works. The best description we have of the. nature of the particles that make up matters and the forces with which they interact. It underlines how atoms work, and so why chemistry and biology work as they do
Let
be the distance between the base of the ladder and the bottom of the wall, and
the distance between the top of the ladder and the bottom of the wall, so that
![x^2+y^2=(25\,\mathrm{ft})^2](https://tex.z-dn.net/?f=x%5E2%2By%5E2%3D%2825%5C%2C%5Cmathrm%7Bft%7D%29%5E2)
Differentiate both sides with respect to time
:
![2x\dfrac{\mathrm dx}{\mathrm dt}+2y\dfrac{\mathrm dy}{\mathrm dt}=0](https://tex.z-dn.net/?f=2x%5Cdfrac%7B%5Cmathrm%20dx%7D%7B%5Cmathrm%20dt%7D%2B2y%5Cdfrac%7B%5Cmathrm%20dy%7D%7B%5Cmathrm%20dt%7D%3D0)
When
, the top of the ladder is
![y=\sqrt{(25\,\mathrm{ft})^2-(20\,\mathrm{ft})^2}=15\,\mathrm{ft}](https://tex.z-dn.net/?f=y%3D%5Csqrt%7B%2825%5C%2C%5Cmathrm%7Bft%7D%29%5E2-%2820%5C%2C%5Cmathrm%7Bft%7D%29%5E2%7D%3D15%5C%2C%5Cmathrm%7Bft%7D)
above the ground. Then, given that the bottom of the ladder slides away from the wall at a rate of
, we have
![2(20\,\mathrm{ft})\left(0.18\dfrac{\rm ft}{\rm s}\right)+2(15\,\mathrm{ft})\dfrac{\mathrm dy}{\mathrm dt}=0\implies\dfrac{\mathrm dy}{\mathrm dt}=-0.24\dfrac{\rm ft}{\rm s}](https://tex.z-dn.net/?f=2%2820%5C%2C%5Cmathrm%7Bft%7D%29%5Cleft%280.18%5Cdfrac%7B%5Crm%20ft%7D%7B%5Crm%20s%7D%5Cright%29%2B2%2815%5C%2C%5Cmathrm%7Bft%7D%29%5Cdfrac%7B%5Cmathrm%20dy%7D%7B%5Cmathrm%20dt%7D%3D0%5Cimplies%5Cdfrac%7B%5Cmathrm%20dy%7D%7B%5Cmathrm%20dt%7D%3D-0.24%5Cdfrac%7B%5Crm%20ft%7D%7B%5Crm%20s%7D)
That is, the top of the ladder is sliding downward at a rate of 0.24 ft/s.
To solve the problem it is necessary to apply the Malus Law. Malus's law indicates that the intensity of a linearly polarized beam of light, which passes through a perfect analyzer with a vertical optical axis is equivalent to:
![I=I_0 cos^2\theta](https://tex.z-dn.net/?f=I%3DI_0%20cos%5E2%5Ctheta)
Where,
indicates the intensity of the light before passing through the polarizer,
I is the resulting intensity, and
indicates the angle between the axis of the analyzer and the polarization axis of the incident light.
Since we have two objects the law would be,
![I=I_0cos^2\theta_1*cos^2(\theta_2-\theta_1)](https://tex.z-dn.net/?f=I%3DI_0cos%5E2%5Ctheta_1%2Acos%5E2%28%5Ctheta_2-%5Ctheta_1%29)
Replacing the values,
![I=100*cos^2(20)*cos^2(40-20)](https://tex.z-dn.net/?f=I%3D100%2Acos%5E2%2820%29%2Acos%5E2%2840-20%29)
![I=100*cos^4(20)](https://tex.z-dn.net/?f=I%3D100%2Acos%5E4%2820%29)
![I=77.91W/m^2](https://tex.z-dn.net/?f=I%3D77.91W%2Fm%5E2)
Therefore the intesity of the light after it has passes through both polarizers is ![77.91W/m^2](https://tex.z-dn.net/?f=77.91W%2Fm%5E2)
Answer:
magnitude of the gravitational force is 9.04 ×
N
Explanation:
given data
altitude = A = 612 km = 612000 m
mass M = 11,100 kg
mass of the Earth m = 5.97 ×
kg
Earth average radius = 6.38 ×
m
to find out
magnitude of the gravitational force
solution
first we get here distance from space to centre of earth that is
distance = altitude + earth radius
distance = 612000 + 6.38 ×
m
distance = 6.99 ×
m
so now we get here magnitude of the gravitational force that is express as
magnitude of the gravitational force F =
...........1
here G is gravitational constant that is 6.67 ×
Nm² /kg and M is mass of space and m is mass of earth
put here all value we get
F =
F =
F = 9.04 ×
N
so magnitude of the gravitational force is 9.04 ×
N