Answer:
option (B)
Explanation:
Intensity of unpolarised light, I = 25 W/m^2
When it passes from first polarisr, the intensity of light becomes
![I'=\frac{I_{0}}{2}=\frac{25}{2}=12.5 W/m^{2}](https://tex.z-dn.net/?f=I%27%3D%5Cfrac%7BI_%7B0%7D%7D%7B2%7D%3D%5Cfrac%7B25%7D%7B2%7D%3D12.5%20W%2Fm%5E%7B2%7D)
Let the intensity of light as it passes from second polariser is I''.
According to the law of Malus
![I'' = I' Cos^{2}\theta](https://tex.z-dn.net/?f=I%27%27%20%3D%20I%27%20Cos%5E%7B2%7D%5Ctheta)
Where, θ be the angle between the axis first polariser and the second polariser.
![I'' = 12.5\times Cos^{2}15](https://tex.z-dn.net/?f=I%27%27%20%3D%2012.5%5Ctimes%20Cos%5E%7B2%7D15)
I'' = 11.66 W/m^2
I'' = 11.7 W/m^2
<span>Inertia keeps us orbiting because any object with mass has the tendency to resist changes to their direction and speed of movement. Combine that with the interaction of the gravitational attraction of the sun, and that is what keeps Earth in orbit. The sun’s gravitational force is one that is proportional to Earth’s mass, and it acts in a way that is almost exactly perpendicular to Earth’s motion. This keeps Earth from spinning into the sun or far away from it.</span>
From the information given above,
Mass [M] = 28 g
Change in temperature = 29 - 7 = 22
Specific heat of iron = 0.449 [This value is constant]
The formula for calculating heat absorbed, Q is
Q = Mass * Specific heat of Iron * change in temperature
Q = 28 * 0.449 * 22 = 276.58 J<span />
A control is something you don't touch/change in a exprement, a constant is the same as the control, the independent is the one the you do vhange, the dependet is the one that you observe/ use your 5 sences with.
Answer:
280 N
Explanation:
acceleration = v2-v1 / time taken = (2-4 )/ 0.05 = -40 m/s^2 ( neg sign indicates slowing down )
force exerted = ma = 7 kg x -40 m/s^2 = - 280 N ( neg sign means opposite direction of initial velocity )
since the 7 kg ball is slowing down, the direction of force will be opposite of the initial velocity , and it will be 280 N