Explanation:
The reason why Marina sees the colour red, white and blue or the original colour of the American flag is that because of a phenomenon known as Afterimage. The retina in our eyes have mainly three receptors that are colour sensitive known as cones. These receptors can perceive the colour green, red and blue. Now when we look or stare at a particular colour for a long time, what happen is that our retina becomes tired and they ignore the colours that stared at. And now they work to form other colours at the retina just like the way when we produce other colour from the primary colour.
If the red receptor gets exhausted we will see the colour red. Likewise when we see the colour orange when we stare at the colour blue.
This explains the optical illusion of the American flag.
Answer:
The number of turns in the solenoid is 230.
Explanation:
Given that,
Rate of change of current, 
Induced emf, 
Current, I = 1.5 A
Magnetic flux, 
The induced emf through the solenoid is given by :

or
........(1)
The self inductance of the solenoid is given by :
.........(2)
From equation (1) and (2) we get :

N is the number of turns in the solenoid


N = 229.28 turns
or
N = 230 turns
So, the number of turns in the solenoid is 230. Hence, this is the required solution.
The reason why Lake Jackson disappeared is A. opening of a sinkhole.
Pollution, high atmospheric temperature, and absorption of water by the land aren't enough for an entire lake to disappear, however, a sinkhole may contribute to that. There are two major depressions (sinkholes) in this lake in Florida, and they even have their own names - Porter Sink and Lime Sink.
Volume will decrease if the heat remains constant
Answer:
The jumper is in freefall for 12.447 seconds.
Explanation:
Let's start by calculating how far the jumper falls.
Initial height (on cliff) = 910 m
Final height after freefall = 150 m
Distance the jumper falls in freefall = 910 - 150 = 760 m
We can now use the equation of motion below to solve for the time:

here. acceleration = 9.81 m/s (due to gravity)
initial speed (u) = 0 m/s (because vertical speed is 0 at the start)
and distance (s) = 760 meters (as calculated above)
So for speed we get:


t = 12.447 seconds