The formula for the energy stored in the magnetic field of an inductor is:
E = (1/2) (inductance) (current)² .
In the present situation:
Energy = (3 kilo-watt-hour) x (1,000 / kilo) x (joule/watt-sec) x (3,600 sec/hr)
= (3 · 1000 · 3,600) (kilo·watt·hr·joule·sec / kilo·watt·sec·hr)
= 1.08 x 10⁷ joules .
Now to find the inductance:
E = (1/2) (inductance) (current)²
(1.08 x 10⁷ joules) = (1/2) (inductance) (300 Amp)²
(2.16 x10⁷ joules) = (inductance) (300 Amp)²
Inductance = (2.16 x10⁷ joules) / (300 Amp)²
= 2.16 x10⁷ / 90,000 Henrys
I get 240 Henrys .
This is a big inductance. Possibly the size of your house.
To get a big inductance, you want to wind the coil
with a huge number of turns of very fine wire, in
a small space.
In this case, however, if you plan on running 300A through
your coil, it'll have to be wound with a very thick conductor ...
like maybe 1/4-inch solid copper wire, or even copper tubing,
You have competing requirements.
There are cheaper, easier, better ways to store 3 kWh of energy.
In fact, a quick back-of-the-napkin calculation says that
3 or 4 car batteries will do the job nicely.
Answer: 4.9 x 10-3 N
Explanation:
A = 500cm^2 = 5 x 10^-2 m^2
V = 5 m/s
R = 10^-3 g/cm^2.sec = 10^-2kg/m^2 . sec
Prain water = R / V = 10^-2 / 5 = 2 x 10-3 kg/m^3
For the stationary bowl,
dm/dt =pAv= RA
F= dp/dt = (dm/dt) v = RAv = 2.5 x 10^-3 N
Bowl moving upwards to speed u = 2 m/s
dm/dt = pA ( v + u) / v
F = dp/dt = (dm/dt)(v+u) = RA (v+u)^2 / v = 4.9 x 10^-3 N
Answer:
True
Explanation:
Gravity is a very important force. Every object in space exerts a gravitational pull on every other, and so gravity influences the paths taken by everything traveling through space. It is the glue that holds together entire galaxies. It keeps planets in orbit.
Answer:
Explanation:
It means any object in free fall due to the gravitational force of the moon, will have an acceleration of 1.66 m/s^2.
