The short answer to how the aurora happens is that energetic electrically charged particles (mostly electrons) accelerate along the magnetic field lines into the upper atmosphere, where they collide with gas atoms, causing the atoms to give off light.
Answer: Lever
A wheelbarrow consists of a lever to be able to lift the material, and a wheel to be able to move it horizontally. So in a sense, a wheelbarrow is a complex machine consisting of two simple machines.
(B)Option b is your answer..........
<span>Distance is a scalar quantity that refers to "how much ground an object has covered" during its motion. Displacement is a vector quantity that refers to "how far out of place an object is"; it is the object's overall change in position.</span>
Answer:
speed of electrons = 3.25 × 
m/s
acceleration in term g is 3.9 × 
g.
radius of circular orbit is 2.76 × 
m
Explanation:
given data
voltage = 3 kV
magnetic field = 0.66 T
solution
law of conservation of energy
PE = KE
qV = 0.5 × m × v²
v = 
v = 
v = 3.25 × m/s
and
magnetic force on particle movie in magnetic field
F = Bqv
ma = Bqv
a = 
a = 
a = 3.82 × 
m/s²
and acceleration in term g
a = 
a = 3.9 × g
acceleration in term g is 3.9 × g.
and
electron moving in circular orbit has centripetal force
F = 
Bqv =
r = 
r = 
r = 2.76 × m
radius of circular orbit is 2.76 × m
