"A capacitor charged to 1.5 V stores 2.0 mJ of energy. Determine the energy stored in the capacitor if it is charged to 3.0 V."

To solve this problem we will apply the concepts related to electric potential energy. This relationship shows us that energy is equivalent to half the product between the capacitance of the body by the squared voltage. Mathematically it can be expressed as,

Here,

C = Capacitance

V = Voltage

E = Energy

The initial capacitance would then be given by

Energy stored in the capacitor with 3V is

Therefore the energy stored in the capacitor if it is charged to 3V is 8mJ

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:

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.