Answer:
Yes, It is true.
The acceleration due to gravity is caused by field force.
Answer:
no, when a plastic rod is rubbed with a duster, electrons are transferred from one material to the other. The material that gains electrons becomes negatively charged. The material that loses electrons becomes positively charged.
Explanation:
Explanation:
When Joe works alone, the total number of words he typed can be given by:
Total words = (40 words per minute) x (60 minutes per hour) x (2.5 hours)
Total words = 6000 words
Now, when Joe and Mark work together, let 'y' be the number of hours for which they both work simultaneously:
Total words = Words Typed by Joe + Words Typed by Mark
6000 = {(40 words per minute) x (60 minutes per hours) x (y hours)} + {(20 words per minute) x (60 minutes per hours) x (y hours)}
6000 = 2400y + 1200y = 3600y
y = 1.67 hours = 1 hour and 40 minutes
Thus, working together simultaneously, Joe and Mark will take 1 hour and 40 minutes to complete the report.
Answer:
B) waves speed up
C) waves bend away from the normal
Explanation:
The index of refraction of a material is the ratio between the speed of light in a vacuum and the speed of light in that medium:
where
c is the speed of light in a vacuum
v is the speed of light in the medium
We can re-arrange this equation as:
So from this we already see that if the index of refraction is lower, the speed of light in the medium will be higher, so one correct option is
B) waves speed up
Moreover, when light enters a medium bends according to Snell's Law:
where
are the index of refraction of the 1st and 2nd medium
are the angles made by the incident ray and refracted ray with the normal to the interface
We can rewrite the equation as
So we see that if the index of refraction of the second medium is lower (
), then the ratio 
is larger than 1, so the angle of refraction is larger than the angle of incidence:
This means that the wave will bend away from the normal. So the other correct option is
C) waves bend away from the normal
No place in the river is characterized like this
