I think it's b..................
Answer:
5.82812 rad/s
Explanation:
L = Length of meter stick = 1 m = 100 cm
= The center of mass of the stick = 
= Angular velocity
Moment of inertia of the system is given by

As the energy in the system is conserved

The maximum angular velocity is 5.82812 rad/s
Answer:

Explanation:
The Coulomb's Law gives the force by the charges:

Let us denote the positon of the charge q on the y-axis as 'y'.
The force between 'Q' and'q' is

where Θ is the angle between
and x-axis.

whereas

Finally, the x-component of the net force is

Answer:
Explanation:
Given an RL circuit
A voltage source of.
V = 108V
A resistor of resistance
R = 1.1-kΩ = 1100 Ω
And inductor of inductance
L = 34 H
After he inductance has been fully charged, the switch is open and it connected to the resistor in their own circuit, so as to discharge the inductor
A. Time the inductor current will reduce to 12% of it's initial current
Let the initial charge current be Io
Then, final current is
I = 12% of Io
I = 0.12Io
I / Io = 0.12
The current in an inductor RL circuit is given as
I = Io ( 1—exp(-t/τ)
Where τ is time constant and it is given as
τ = L/R = 34/1100 = 0.03091A
So,
I = Io ( 1—exp(-t/τ))
I / Io = ( 1—exp(-t/τ))
Where I/Io = 0.12
0.12 = 1—exp(-t/τ)
0.12 — 1 = —exp(-t/τ)
-0.88 = -exp(-t/0.03091)
0.88 = exp(-t/0.03091)
Take In of both sides
In(0.88) = In(exp(-t/0.03091)
-0.12783 = -t/0.030901
t = -0.12783 × 0.030901
t = 3.95 × 10^-3 seconds
t = 3.95 ms
B. Energy stored in inductor is given as
U = ½Li²
So, the current at this time t = 3.95ms
I = Io ( 1—exp(-t/τ))
Where Io = V/R
Io = 108/1100 = 0.0982 A
Now,
I = Io ( 1—exp(-t/τ))
I = 0.0982(1 — exp(-3.95 × 10^-3 / 0.030901))
I = 0.0982(1—exp(-0.12783)
I = 0.0982 × 0.12
I = 0.01178
I = 11.78mA
Therefore,
U = ½Li²
U = ½ × 34 × 0.01178²
U = 2.36 × 10^-3 J
U = 2.36 mJ
I would have to say that 'B' and 'D' are both correct.
Increasing the voltage that you're using to operate a circuit
causes the current in the circuit to increase. But current is
just the number of electrons that are flowing through it. So
right there, you have the increase in the number of charges.
Now, every electron that flows through the circuit gives up
some energy on the way. So if there are more electrons
making the trip, then more energy has been put into the circuit.
Jessica, I absolutely love your printing.
I wish I could print so clearly.