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3 years ago

Definition of fluoresence

2 answers:

5 0

The visible or invisible radiation emitted by certain substances as a result of incident radiation of a shorter wavelength such as x-rays or ultraviolet light

denis23 [38]3 years ago

4 0

Answer:

the property of absorbing light of short wavelength and emitting light of longer wavelength.

Explanation:

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Will give the first answer brainliest. Picture attached.

mylen [45]

Answer:

2699.73661Ω or 2.697kΩ

Explanation:

$V=IR$

So...

$R=\frac{V}{I}$

So...

$\frac{12.3}{0.004556} = 2699.73661$ Ω

This is the answer, but the resistance is much too high for a circuit like this

4 0

3 years ago

An inventive child named Nick wants to reach an apple in a tree without climbing the tree. Sitting in a chair connected to a rop

jeyben [28]

A) diagram is shown on the image below

b) Mass m = 450/9.8 = 45.918 KgNet upward force = T + T = 2T = 620 NNet downward force = 290 + 160 = 450 NResultant force F = Net upward force - Net downward force ma = 620 - 450 45.918 a = 170 Acceleration a = 170/45.918 = 3.7 m/s^2 (upward)Here Net upward force > Net downward force, So the resultant force directed upwards, hence acceleration will be upward.

(c)Consider the case of boy alone, then from Newtons law of motion we can write Net force F = n + T - 290 ma = n + 310 - 290 where m = 290/9.8 = 29.59 Kg 29.59 * 3.7 = n + 20 109.483 = n + 20 n = 89.483 N

4 0

4 years ago

The image formed by a plane mirror are always of ....... size.

Elanso [62]

Answer:

same

step by step explanation:

5 0

3 years ago

A ceramic tile measuring 50 cm x50cm has been designed to bear a pressure of 40 N/in . Will it with stand a force of 5 N?

dangina [55]

Answer:

The ceramic tile will stand the force of 5 N.

Explanation:

Step 1: Calculate the area (A) of the ceramic tile

We will use the formula for the area of a square.

A = 50 cm × 50 cm = 2500 cm²

Step 2: Convert "A" to in²

We will use the conversion factor 1 in² = 6.45 cm².

2500 cm² × 1 in²/6.45 cm² = 3.9 × 10² in²

Step 3: Calculate the pressure (P) exerted by a force (F) of 5 N

We will use the following expression.

P = F/A

P = 5 N / 3.9 × 10² in² = 0.013 N/in²

Since the pressure exerted would be less than the maximum pressure resisted (40 N/in²), the ceramic tile will stand the force of 5 N.

3 0

3 years ago

A Brayton cycle has air into the compressor at 95 kPa, 290 K, and has an efficiency of 50%. The exhaust temperature is 675 K. Fi

motikmotik

Answer:

The specific heat addition is 773.1 kJ/kg

Explanation:

from table A.5 we get the properties of air:

k=specific heat ratio=1.4

cp=specific heat at constant pressure=1.004 kJ/kg*K

We calculate the pressure range of the Brayton cycle, as follows

n=1-(1/(P2/P1)^(k-1)/k))

where n=thermal efficiency=0.5. Clearing P2/P1 and replacing values:

P2/P1=(1/0.5)^(1.4/0.4)=11.31

the temperature of the air at state 2 is equal to:

P2/P1=(T2/T1)^(k/k-1)

where T1 is the temperature of the air enters the compressor. Clearing T2

11.31=(T2/290)^(1.4/(1.4-1))

T2=580K

The temperature of the air at state 3 is equal to:

P2/P1=(T3/T4)^(k/(k-1))

11.31=(T3/675)^(1.4/(1.4-1))

T3=1350K

The specific heat addition is equal to:

q=Cp*(T3-T2)=1.004*(1350-580)=773.1 kJ/kg

3 0

3 years ago