Answer:



Explanation:
<u>Simple Pendulum</u>
It's a simple device constructed with a mass (bob) tied to the end of an inextensible rope of length L and let swing back and forth at small angles. The movement is referred to as Simple Harmonic Motion (SHM).
(a) The angular frequency of the motion is computed as

We have the length of the pendulum is L=0.81 meters, then we have


(b) The total mechanical energy is computed as the sum of the kinetic energy K and the potential energy U. At its highest point, the kinetic energy is zero, so the mechanical energy is pure potential energy, which is computed as

where h is measured to the reference level (the lowest point). Please check the figure below, to see the desired height is denoted as Y. We know that

And

Solving for Y



The potential energy is


The mechanical energy is, then


(c) The maximum speed is achieved when it passes through the lowest point (the reference for h=0), so the mechanical energy becomes all kinetic energy (K). We know

Equating to the mechanical energy of the system (M)

Solving for v


Answer:
magnitude: 21.6; direction: 33.7 degrees
Explanation:
When we multiply a vector by a scalar, we have to multiply each component of the vector by the scalar number. In this case, we have
vector: (-3,-2)
Scalar: -6
so the vector multiplied by the scalar will have components

The magnitude is given by Pythagorean's theorem:

and the direction is given by the arctan of the ratio between the y-component and the x-component:

Answer:
The dynamo produces Alternating Current output, so in theory yes, it should work in reverse if Alternating Current is input.
Answer:
I think that when a book hits the ground its potential energy converts into kinetic energy and then kinetic energy is transformed into sound and heat energy.
Explanation:
Answer:
The current is 0.248 A
Explanation:
Given that,
Inductor 
Resistance 
Voltage = 15 volt
Time 
We need to calculate the current
Using formula of current

Where, V = voltage
R = resistance
L = inductance
T = time
Put the value into the formula


Hence, The current is 0.248 A.