Speed = distance/time taken
1484 = distance/3
Distance = 1484 x 3
Distance = 4452 m
Answer:
its obviously D if all the other says "incorrect answer" XD
Explanation:
Answer:
The minimum thickness of the oil is 77.55 nm
Explanation:
Given:
Refractive index of oil 
Refractive index of water 
Wavelength of light
m
From the equation of thin film interference,
The minimum thickness is given by,

Where
,
thickness
Here we have to find minimum thickness so we use



m
nm
Therefore, the minimum thickness of the oil is 77.55 nm
Energy at top = U = mgh = 40 * 9.8 * 12 = 4704 J
Energy at bottom = 1/2 mv² = 1/2 * 40 * 10² = 4000 / 2 = 2000 J
Energy Lost = Final - Initial = 4704 - 2000 = 2704 J
In short, Your Answer would be 2704 Joules
Hope this helps!