Answer:
Law of refraction
Explanation:
An experiment to analyze the refraction of light in water can easily be performed with a laser pointer and protractor.
We throw the fishing rod line into the water, place the protractor at the point where the line touches the water and use the direction of the line for the direction of the laser pointer (on), the laser is visible by the reflection on the particles in the air.
The vertical line is called Normal and all angles must be measured with respect to this reference in optics.
Having these angles and the refractive index of water we can use the law of refraction
n₁ sin θ₁ = n₂ sin θ₂
θ₂ = 
we can repeat several times to analyze several different input points (different angles) and to decrease the errors in the measurements.
the refractive index of air is n1 = 1 and n2= 1.33 (water)
Answer:
For Total energy and momentum to be conserved, the minimum energy of the photons released is equal to twice the rest mass energy of an electron that is 
The annihilation of electron -positron cannot produce a single photon. It is prohibited by the law of conservation of energy and momentum.
Answer:
Soory
Explanation:
I really dont know but i will send you wait
Answer:
Explanation:
A plane flies due north (90° from east) with a velocity of 100 km/h for 2 hours.
With no wind, it will be 100*2 = 200 km north of its starting point.
But a steady wind blows southeast at 30 km/h at an angle of 315° from due east.
So the wind itself will blow the plane 30*2 = 60km at an angle of 315° from due east.
That is the same as 60*cos315° = 42.43km due east and 60*sin315° = -42.43km north.
Combining, the plane is at 42.43km due east and 200-42.43 = 157.57km due north from its starting point.
