Two square air-filled parallel plates that are initially uncharged are separated by 1.2 mm, and each of them has an area of 190 mm^2. how much charge must be transferred from one plate to the other if 1.1 nj of energy are to be stored in the plates? ( ε0 = 8.85 × 10^-12 c2/n · m^2)

Explanation:

The capacitance of the parallel-plate capacitor is given by:

where

is the vacuum permittivity

is the area of the plates

is the separation between the plates

Substituting,

The energy stored in the capacitor is given by

Since we know the energy

we can re-arrange the formula to find the charge, Q:

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

1 a

2 b

3 b

4 d

5 d

6 d

explanation: