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:
The jug drowns because the density of the jug is more than that of the density of water.
Answer:
Explanation:
Radius of dee, r = 8 mm = 0.008 m
Electric field, e = 400 V/m
Magnetic field, B = 4.7 x 10^-4 T
mass of electron, m = 9.1 x 10^-31 kg
charge of electron, q = 1.6 x 10^-19 C
(a) Let v is the speed of electrons.


v = 661098.9 = 661099 m/s
(b)

e / m = 1.76 x 10^14 C / kg
(c) Let K be the kinetic energy
K = 0.5 x mv²
K = 0.5 x 9.1 x 10^-31 x 661099 x 661099
K = 1.99 x 10^-19 J
K = 1.24 eV
So, the potential difference is
V = 1.24 V
(d) if the acceleration voltage is doubled
V = 2 x 1.24 = 2.48 V
So, Kinetic energy
K = 2.48 eV
K = 2.48 x 1.6 x 10^-19 = 3.968 x 10^-19 J
Let v is the speed
K = 0.5 x mv²
3.968 x 10^-19 = 0.5 x 9.1 x 10^-31 x v²
v = 933856.5 m/s
Let the new radius is r.


r = 0.0113 m = 1.13 cm
Answer:
the centripetal force on the satellite in the larger orbit is _one fourth_ as that on the satellite in the smaller orbit.
Explanation:
Mass of satellite, m
orbit radius of first, r1 = r
orbit radius of second, r2 = 2r
Centripetal force is given by

Where v be the orbital velocity, which is given by

So, the centripetal force is given by

where, g bet the acceleration due to gravity

So, the centripetal force

Gravitational force on the satellite having larger orbit
.... (1)
Gravitational force on the satellite having smaller orbit
.... (2)
Comparing (1) and (2),
F' = 4 F
So, the centripetal force on the satellite in the larger orbit is _one fourth_ as that on the satellite in the smaller orbit.
The power of the engine is 320 W.
<u>Explanation:</u>
Power may be defined as the rate of doing work (or) work done per unit time. One unit of energy is used to do the one unit of work.
Power = Work done / Time taken
Given, Force = 80 N, height = 5 m , final velocity = 4 m/s
To calculate the power, we must know the time taken.
To find the time, use the distance and speed formula which is given by
Time = Distance / speed
Here distance = 5 m and speed = 4 m/s
Time = 5 / 4 = 1.25 s.
Now, Power = work done / time
= (F * d) / t = (80 * 5) / 1.25
Power = 320 W.
The standard unit of power is watt (W) which is joule per second.