7.5 I think because it can not be 9 because it’s not close to 50
Here in all such collision type question we can use momentum conservation as we can see that there is no external force on this system

as we know that




now from above equation we have



so the speed of combined system is 2 m/s
Answer:
Water
Explanation:
windmills were used to bring water to farms in ancient times.
Answer:
energy is converted into mass
Explanation:
Answer:
Angle θ = 30.82°
Explanation:
From Malus’s law, since the intensity of a wave is proportional to its amplitude squared, the intensity I of the transmitted wave is related to the incident wave by; I = I_o cos²θ
where;
I_o is the intensity of the polarized wave before passing through the filter.
In this question,
I is 0.708 W/m²
While I_o is 0.960 W/m²
Thus, plugging in these values into the equation, we have;
0.708 W/m² = 0.960 W/m² •cos²θ
Thus, cos²θ = 0.708 W/m²/0.960 W/m²
cos²θ = 0.7375
Cos θ = √0.7375
Cos θ = 0.8588
θ = Cos^(-1)0.8588
θ = 30.82°