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3 years ago

6

About how long have wastewater treatment plants been in existence? about how long have wastewater treatment plants been in exist

ence? 50 years 120 years 190 years 220 years 300 years

1 answer:

ella [17]3 years ago

8 0

Water treatment plants have been in existence for almost 220 years

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5. The ends of a 10 cm laser rod, index of refraction = 1.76, has its ends coated for reflectivity of 99.9 % and 90 %. If there

Jobisdone [24]

Answer:

the fractional loss per pass =0.053

the decay time of the cavity =11 ns

Explanation:

laser is an acronym for Light Amplification by Stimulated Emission of Radiation and it has lot of military applications : basically ranging from target acquisition, fire control, and training. It is also being used in LIDAR communications, radar systems , laser guided landing systems, laser pointers, holography, photography, guidance systems, scanning machines, metal working, and medicine.

the fractional loss per pass= $\alpha l - ln(R_1R_2)^ \frac {1}{2}$

but no excited state absorption, therefore $\alpha$ is 0

$= - ln(R_1R_2)^ \frac {1}{2}\\\\=- ln(0.999* 0.9)^ \frac {1}{2}$

=0.053

b) the decay time of the cavity:

$T_c = \frac{nd}{cl_f}=\frac{1,76 * 10 *10^-2}{3 *10^8 *0.53}$

=1.1 *10^-8 seconds

=11 ns

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3 years ago

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telo118 [61]

i believe the answer is C.

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3 years ago

The base ( foundation ) of building is made wider. Why ?

attashe74 [19]

Answer: It is increased to exert the pressure off the bywalls and on large area (brainliest pls)

Explanation: ...

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2 years ago

Anyone know this... pls help its for a grade

hodyreva [135]

His average speed is 45 miles an hour

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2 years ago

A uniform sphere (I = 2/5 MR 2 ) rolls down an incline. (a) What must be the incline angle if the linear acceleration of the cen

Liono4ka [1.6K]

Answer:

Part a)

$\theta = 8.05 degree$

Part b)

$a = 1.37 m/s^2$

Explanation:

As the uniform sphere is rolling down the inclined plane then the net force on the sphere is given as

$mg sin\theta - F_f = ma$

also we have torque equation on it

$F_f R = I\alpha$

for pure rolling

$a = R \alpha$

$F_f = \frac{Ia}{R^2}$

now we have

$mg sin\theta = ma + \frac{Ia}{R^2}$

now we have

$mg sin\theta = (m + \frac{2}{5}m)a$

$a = \frac{5}{7}g sin\theta$

now given that

$a = 0.10 g$

so we have

$0.10 g = \frac{5}{7} g sin\theta$

$sin\theta = 0.14$

$\theta = 8.05 degree$

Part b)

If the inclined plane is frictionless then the acceleration is given as

$a = g sin\theta$

$a = 9.8(0.14)$

$a = 1.37 m/s^2$

5 0

3 years ago

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