Answer:
The statement as aurora australis known as northern lights is incorrect. As the designation of aurora australis is for the southern lights i.e. which occur in the southern hemisphere.
Explanation:
Aurora or natural lights is a phenomenon that occurs at the poles of the Earth due to interaction between the Earth's magnetic field and cosmic rays. This interaction results in the beautiful display of colors on both poles. These are named, aurora borealis or aurora australis depending on their geographical location. If they occur on the northern pole they are termed as aurora borealis while those occurring on the southern pole are named aurora australis.
Answer:
0.23348 A
Explanation:
B = Magnetic field
v = Velocity of electron = 
q = Charge of electron = 
= Vacuum permeability = 
r = Radius of circle = 0.026 m
N = Number of turns = 103 turns/cm = 
I = Current
The magnetic and centripetal force will be balanced

The magnetic field in solenoid is given by

From the first equation

The current in the solenoid is 0.23348 A
Explanation:
The ratio of the areas is the square of the ratio of the radii.
A/A = 3.16² = 9.99
The ratio of the volumes is the cube of the ratio of the radii.
V/V = 3.16³ = 31.6
Answer:
7772.72N
Explanation:
When u draw your FBD, you realize you have 3 forces (ignore the force the car produces), gravity, normal force and static friction. You also realize that gravity and normal force are in our out of the page (drawn with a frame of reference above the car). So that leaves you with static friction in the centripetal direction.
Now which direction is the static friction, assume that it is pointing inward so
Fc=Fs=mv²/r=1900*15²/55=427500/55=7772.72N
Since the car is not skidding we do not have kinetic friction so there can only be static friction. One reason we do not use μFn is because that is the formula for maximum static friction, and the problem does not state there is maximum static friction.
Protons and Neutrons account for most of an atoms mass