Answer:
Explanation:
The rms voltage = 140/√2 = 140/1.414 = 99 V.
Reactance of inductor = wL = 2 X 3.14 X 100 X 113 X 10⁻³ =70.96 ohm.
Total resistance in terms of vector = 50+70.96j
j is imaginary unit number
Magnitude of this resistance = √ 50² + 70.96² = 86.80 ohm
current in resistance (rms) ( I ) = 99/86.80 = 1.14 A.
Power dissipated in resistor = I² R = 1.14 X 1.14 X 50 = 65 W( approx)
Answer:
a) T = 2.26 N, b) v = 1.68 m / s
Explanation:
We use Newton's second law
Let's set a reference system where the x-axis is radial and the y-axis is vertical, let's decompose the tension of the string
sin 30 =
cos 30 =
Tₓ = T sin 30
T_y = T cos 30
Y axis
T_y -W = 0
T cos 30 = mg (1)
X axis
Tₓ = m a
they relate it is centripetal
a = v² / r
we substitute
T sin 30 = m
(2)
a) we substitute in 1
T =
T =
T = 2.26 N
b) from equation 2
v² =
If we know the length of the string
sin 30 = r / L
r = L sin 30
we substitute
v² =
v² =
For the problem let us take L = 1 m
let's calculate
v =
v = 1.68 m / s
Answer:
The first diffraction maximum fringe will be at approximately 2.7 meters from the central maximum.
Explanation:
We can describe single slit diffraction phenomenon with the equation:
(1)
with θ the angular position of the minimum of order m respect the central maximum, a the slit width and λ the wavelength of the incident light. Because the distances between the first minima and the central maximum (
) are small compared to the distance between the screen and the slit (x), we can approximate
, using this on (1):

solving for y

Note that
is the distance between a minimum and the central maximum but we need the position of a maximum not a minimum, here we can use the fact that a maximum is approximately between two minima, so the first diffraction maximum fringe is between the minima of order 1 and 2, so we should find
,
add them and divide by two:





The phenomenon is called "refraction". It's the process of
light waves bending toward a different direction when they
cross a boundary between different media ... in this case,
from water into air.
Your brain doesn't know that the light waves bent toward a
new direction when they came out of the water into the air,
so your brain locates the bottom half of the pencil just like it
ALWAYS does ... in the direction the light waves are coming FROM.