Answer:
18.7842493212 W
Explanation:
T = Tension = 1871 N
= Linear density = 3.9 g/m
y = Amplitude = 3.1 mm
= Angular frequency = 1203 rad/s
Average rate of energy transfer is given by

The average rate at which energy is transported by the wave to the opposite end of the cord is 18.7842493212 W
Please mark me as Brainliest ......
No. Science is all about facts and experiments. Making stuff up would go against that, and wouldn't be science.
When a body performs a uniform circular motion, the direction of the velocity vector changes at every moment. This variation is experienced by the linear vector, due to a force called centripetal, directed towards the center of the circle that gives rise to centripetal acceleration, the mathematical expression is given as,

Where,
v = Tangential Velocity
r = Radius
The linear velocity was 2010m/s in a radius of 0.159m, then the centripetal acceleration is


Therefore the centripetal acceleration of the end of the rod is 
Answer:
1) The medium b has higher optical density.
2) If the optical densities of both A and B are same.
Explanation:
- The refractive index of a material determines the number of times the velocity of light in that material is slower than the velocity of light in a vacuum.
- The higher refractive index means slower propagation of the light in that medium.
- The refractive index of the medium determines the optical density of the medium.
- If the material has a higher refractive index, then its optical density is high.
- If the material has a low refractive index, then its optical density is low.
- The light bends towards the normal while refracting through the medium from a lower optical density medium to the higher optical density medium.
- If both the mediums has the same optical density, the direction of propagation doesn't change.