Answer:
<h2>index of refraction = 1.69</h2><h2>percentage error = 10.58%</h2>
Explanation:
According to Snell's law, the ratio of the sine of angle of incidence to the sine of angle of refraction is a constant for a given pair of media. The constant is known as the refractive index.
Mathematically 
i = angle of incidence measured = 63.5°
r = angle of refraction measured = 32°
n = refractive index

The index fraction calculated is approx. 1.69.
If the index of refraction of a clear plastic as listed in the book is 1.89 and the calculated is 1.69, the percentage error will be calculated as thus;
%error = 
%error = 
%error = 
%error = 10.58%
Answer:
162.78 m/s is the most probable speed of a helium atom.
Explanation:
The most probable speed:

= Boltzmann’s constant =
T = temperature of the gas
m = mass of the gas particle.
Given, m = 
T = 6.4 K
Substituting all the given values :


162.78 m/s is the most probable speed of a helium atom.
Answer:
acceleration
Explanation:
acceleration =velocity final-velocity initial /time
1. Is A. at the poles because thats where the magnetic field is going out then coming back into the earth to produce the magnetic field.
2. Again its A. because the compass needle is attracted to " north " which is magnetic south. It does this because opposites attract.
3. This one would be B. Because if the magnets were being repelled the magnetic field lines would look like there was a line that the field hit and bounced off of it.
4. This answer is A. the magnetite helps them migrate so they know which way is north and which way is south.
5. This answer is A. Because without the domains there wouldn't be poles on the magnetic object. <span />
Answer:
Sound wave is a longitudinal wave that propagates in a medium
Explanation:
<em>Part A:</em> (C) Sound wave is propagation of pressure fluctuations in a medium.
<em>Part B: </em>(C) Pressure fluctuations travel along the direction of propagation of the sound wave.
<em>Part C: </em>(A) Yes air play a role in the propagation of the human voice from one end of the lecture hall to the other.