Final answer:
The apparent height of the coin from the water surface as seen by Ria underwater is 1.13 meters.
Step-by-step explanation:
When an object is submerged in water, its apparent height as observed from a different medium, such as air, appears to be different than its actual height. This phenomenon is due to the refraction of light as it passes from one medium to another. To find the apparent height of the coin from the water surface as seen by Ria underwater, we need to use the concept of refraction.
The apparent height of the coin can be found using the formula:
Apparent height = Actual height / Refractive index
In this case, since the coin is in the air and the observer (Ria) is underwater, the refractive index needed is the refractive index of water.
Using nair and nwater as the refractive indexes of air and water respectively, the formula becomes:
Apparent height = Actual height * (nair / nwater)
Refractive index of air (nair) is approximately 1 and the refractive index of water (nwater) is 1.33. Let's calculate:
Apparent height = 1.5 m * (1 / 1.33) = 1.13 m
Therefore, the apparent height of the coin from the water surface as seen by Ria underwater is 1.13 meters.