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3 years ago

7

A tuning fork with a frequency of 675 Hz resonates in an air column when the length of the tube is 17.0 cm and again when the le

ngth is 43.0 cm. The wavelength of the standing wave in the air column is ___cm

1 answer:

maria [59]3 years ago

8 0

Answer:

Explanation:

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Find the currents flowing in the circuit in the figure below. (Assume the resistances are

Nitella [24]

By Kirchoff's law in left side loop

$E_1 + E_2 = {r_1 + R_1 + R_4)I_1 + (R_2 + r_2) I_3$

similarly kirchoff's law in right side loop

$E_3 - E_4 - E_2 = (r_3 + r_4 + R_3)I_2 - (R_2 + r_2)I_3$

also by junction law we know that

$I_1 = I_2 + I_3$

now by plug in all values we have

$18 + 3 = (0.5 + 8 + 15)I_1 + (10 + 0.25)I_3$

$21 = 23.5I_1 + 10.25I_3$

$12 - 24 - 3 = (0.75 + 0.25 + 12)I_2 - (10+ 0.25)I_3$

$-15 = 13I_2 - 10.25I_3$

So by solving above equations we have

$I_1 = 0.492 A$

$I_2 = -0.428 A$

$I_3 = 0.920 A$

6 0

4 years ago

Red Sox designated hitter, David Ortiz, swings at a 0.15 kg baseball and accelerates it at a rate of 3.0 • 10^4 m/s^2. How much

aivan3 [116]

Answer:

Explanation:

A lot. That's why he was one of Boston's star hitters.

m = 0.15 kg

a = 3.0 * 10^4

F = ?

F = 0.15 * 3*10^4

F = 0.45 * 10^4

F = 4.5 * 10^3 Newtons

You should always express scientific notation as a number between 1 and 10 or 1 < x < 10. The power will determine the exact value of the number expressed as a scientific notation.

3 0

3 years ago

Freeeeeeeee poinnttttsssss

RUDIKE [14]

Answer:

k

Explanation:

umm really

5 0

3 years ago

We can reasonably model a 90-W incandescent lightbulb as a sphere 5.7 cm in diameter. Typically, only about 5% of the energy goe

o-na [289]

Answer:

See answer

Explanation:

Given quantities:

$\eta = 0.05\\ W=90[W]\\r=0.0285[m]$

where $\eta$ is the efficiency of the lightbulb (visible light is 5% of the total power), $W$ is the total power of the lightbulb, r is the radius of the lightbulb in meters.

Intensity is power divided by area:

$I =\frac{P}{A}$

a) Now the effective power is $\eta*W$ , therefore:

$I =\frac{\eta*W}{\pi r^2}=\frac{0.05*90}{4\pi (0.0285)^2}=440.87[W/m^2]$

b) Now the intensity is the average poynting vector is related to the magnitudes of the maximum electric field and magnetic field amplitudes, following:

$S_{average}= \frac{EB}{2\mu_{0}}[W/m]$

now $E$ and $B$ are related:

$E=cB\\ B=\frac{E}{c}$ and $c=\frac{1}{\sqrt{\epsilon_{0} \mu_{0}}}$

replace in $S_{average}$

$S_{average}=I= \frac{c \epsilon_{0}E^2}{2}[W/m]$

we replace the values and we get:

$E= \sqrt{\frac{2I}{\epsilon_{0}c}}$

$E = \sqrt{\frac{2(440.8)}{8.85*10^{-12}3*10^8}}=576.24[V/m]$

therefore

$B=\frac{E}{c}=\frac{576.24}{3*10^{8}}=1.92*10^{-6}[T]$

8 0

3 years ago

Two electronics technicians are discussing conductors and insulators. Technician A says that conductors have more free electrons

vitfil [10]

Technician A is Correct.

You can see this when he says that conductors have more free electrons than insulators. This statement is True.

While Technician B says that, insulators have the lower resistance than conductors. This statement is False.

4 0

3 years ago

Read 2 more answers