There are two conditions necessary for total internal reflection, which is when light hits the boundary between two mediums and reflects back into its original medium:
Light is about to pass from a more optically dense medium (slower) to a less optically dense medium (faster).
The angle of incidence is greater than the defined critical angle for the two mediums, which is given by:
θ = sin⁻¹(
/
)
Where θ = critical angle,
= refractive index of faster medium,
= refractive index of slower medium.
Choice C gives one of the above necessary conditions.
Explanation: Yes, If you digest something, it will flow from inside your neck into a tube that goes into stomach.
Hope this helps! :D
-TanqR
Answer:
The correct answer is A
Explanation:
The question requires as well the attached image, so please see that below.
Coulomb's Law.
The electrical force can be understood by remembering Coulomb's Law, that describes the electrostatic force between two charged particles. If the particles have charges
and
, are separated by a distance r and are at rest relative to each other, then its electrostatic force magnitude on particle 1 due particle 2 is given by:

Thus if we decrease the distance by half we have

So we get

Replacing we get

We can then multiply both numerator and denominator by 4 to get

So we have

Thus if we decrease the distance by half we get four times the force.
Then we can replace the second condition

So we get

which give us

Thus doubling one of the charges doubles the force.
So the answer is A.
The Net Force would be 2 N to the left.
21 N is being used to push the box to the right and 23 N is used to push it left. There is a stronger force pushing the box towards the left. The different in the two numbers would give you the net force acting on the box and the direction of the arrow with the greatest force will tell you the direction.