The potential energy of a 30N ball on the ground will be zero. With respect to height, h. Potential energy will be calculated like this. P=mgh. So if its on the ground relatively speaking the h=0. Thus inputting into the above formula. P=0.
Answer:
1. To determine the average speed for the first day of the trip, the total distance traveled would have to be acquired and then how long it took to arrive at the final destination, only including the time that was actually traveled and not any time that was accumulated by any rest stops. Once you have this information, you have to divide the distance over time and you have the average speed (mph).
2. To determine the instantaneous speed, you would just have to look at the speedometer, which tells you at what speed the car is traveling at that exact moment.
Explanation:
I took physics 121 and got the same question. This is my answer that i used and my teacher said it was right.
The electrostatic force between two charges q1 and q2 is given by

where

is the Coulomb's constant and r is the distance between the two charges.
If we use F=19.2 N and q1=q2=-3.0 C, we can find the value of r, the distance between the two charges by re-arranging the previous formula:
Answer:
amplifying signals is the correct answer
Explanation:
Explanation:
a)Snell's law states that when light travels from a rarer to a denser substance, like air to water or from a less dense layer of the atmosphere to a denser layer, it bends towards the normal{an imaginary line that is perpendicular to the surface of both media}. However,the opposite occurs when light moves from a more dense to a less dense medium. The angle between the normal and the refracted light ray is known as the angle of refraction.
In case of earth as light from the stars enters the earth atmosphere it bends towards smaller angle because the earth density increases as the light travel towards the earth troposphere from the exosphere as per the Snell's law described above.
b)Light rays that travel straight down do not bend, while rays that enter the Earth's atmosphere at a shallower angle get refracted and bend towards the normal, roughly following the direction of the Earth's curvature.
This means that celestial objects in the zenith position directly above you appear in the correct position, while objects closer to the horizon appear to be higher up in the sky than they actually are.