Here's a formula that's simple and useful, and if you're really in
high school physics, I'd be surprised if you haven't see it before.
This one is so simple and useful that I'd suggest memorizing it,
so it's always in your toolbox.
This formula tells how far an object travels in how much time,
when it's accelerating:
Distance = (1/2 acceleration) x (Time²).
D = 1/2 A T²
For your student who dropped an object out of the window,
Distance = 19.6 m
Acceleration = gravity = 9.8 m/s²
D = 1/2 G T²
19.6 = 4.9 T²
Divide each side by 4.9 : 4 = T²
Square root each side: 2 = T
When an object is dropped in Earth gravity,
it takes 2 seconds to fall the first 19.6 meters.
Answer: 29.5 days
The waxing moon phase comprises three separate moon phases: the Waxing Crescent, First Quarter, and the Waxing Gibbous.
The magnitude of the source charge is 3 μC which generates 4286 N/C of the electric field. Option B is correct.
What does Gauss Law state?
It states that the electric flux across any closed surface is directly proportional to the net electric charge enclosed by the surface.
Where,
= electric force = 4286 N/C
= Coulomb constant = 
= charges = ?
= distance of separation = 2.5 m
Put the values in the formula,
Therefore, the magnitude of the source charge is 3 μC.
Learn more about Gauss's law:
brainly.com/question/1249602
