Answer:
1. The best definition of refraction is ____.
a. passing through a boundary
b. bouncing off a boundary
c. changing speed at a boundary
d. changing direction when crossing a boundary
Answer: D
Bouncing off a boundary (choice b) is reflection. Refraction involves passing through a boundary (choice a) and changing speed (choice c); however, a light ray can exhibit both of these behaviors without undergoing refraction (for instance, if it approaches the boundary along the normal). Refraction of light must involve a change in direction; the path must be altered at the boundary.
With another person on student A’s side. I’m sorry if I wasn’t able to help. Im trying my best from the information given. :)
You have a photo? I could help you if you show me a picture!
Answer:

Explanation:
The ball is moving in a circle, so the force is centripetal.
One formula for calculating centripetal force is:

The mass of the ball is 0.5 kilograms. The radius is 1.9 meters. The centripetal force is 85 Newtons or 85 kg*m/s².
= 85 kg*m/s²- m= 0.5 kg
- r= 1.9 m
Substitute the values into the formula.

Isolate the variable v. First, multiply both sides by 1.9 meters.



Divide both sides by 0.5 kilograms.



Take the square root of both sides of the equation.



The original measurements have 2 significant figures, so our answer must have the same.
For the number we found, 2 sig fig is the ones place. The 9 in the tenth place tells us to round the 7 to an 8.

The maximum speed is approximately <u>18 meters per second.</u>
The answer is B tell me if I am wrong.