According to the principle that the emission lines of a substance must be at exact same positions of its absorption spectrum, what substance accounts for the dark lines in the absorption spectrum

Answer:

Air.

Explanation:

To know which option is correct, let us consider the relationship between velocity and the wavelength of a wave. This is illustrated below:

Velocity, wavelength and frequency are related by the following equation:

Velocity = wavelength × frequency

v = λf

From the equation above, we can see clearly that the velocity is directly proportional to the wavelength.

This means that an increase in the wavelength will lead to an increase in the velocity and also, a decrease in the wavelength will lead to a decrease in the velocity.

Now, considering the table given in the question above, we can see that the wave has a higher speed in air. This simply means that the wave will also have a higher wavelength in air.

Thus, the correct answer to the question is: air

Answer:

English only

Explanation:

When solving problems related to Electric Fields, care must be taken about symmetries. In our particular case when we take a look to at the drawings of the attached file, we realize:

1.-By symmetry each dx associated at a, has an opposite dx with point b as reference. The respective dE ( the charge is uniform ) is the same, as the charge of the wire is positive the force and the Field on a test charge (+) located at h will be upward, therefore the components dEx will cancel each other and the Electric Field becomes E = Ey = ∫ 2×dE× cosθ

The solutions:

A) Ey = 4623 N/C

B) Ey = 19.34 N/C

E = Ey = ∫ 2×dE× cosθ

Here     cosθ   = h/ d   ⇒  cosθ = h/√h² + x²      dE = K× dQ / d²

d² = h² + x²

k = 8.9 ×10⁹ Nm²C⁻²  ;   dQ = λ×dx     λ = 150×10⁻⁹ C    h = 0.08 m

Then by substitution

Ey =  2 ∫[K× λ×dx/ (h² + x²) ] × h / √h² + x²

reordering that equation:

Ey = 2×K×λ×h ∫ dx / [√ ( h² + x² ) ]³          (2)

To solve the integral we make use of a change of variables

x = h × tanα     then   x² = h² ×tan²α   and  dx = h× sec²α dα

plugging that values in equation (2)

Ey  =  2×K×λ×h ∫  h× sec²α× dα / [√ ( h² + h²tan²α)]³

Ey  = 2×K×λ×h² ∫ sec²α× dα / [ h × √ (1 + tan²α)]³            1 + tan²α = sec²α

Ey = 2×K×λ×h²× ∫ (sec²α / h³× sec³α )×dα

Ey = 2×K×λ/h × ∫ ( 1 / secα dα

Ey = 2×K×λ/h × sinα             now we αneed to come back to our original variables:

as   x = h × tanα         tanα = x/h   then x is the opposite leg in a right triangle  and h the adjacent one then the hypothenuse is √ (h² + x²)         then    sin α = x/ √ (h² + x²)      

Ey = 2×K×λ/h × x/ √ (h² + x²) |₀⁰°⁰⁵

Ey  = 2×8.9×10⁹× 150×10⁻⁹× 5×10⁻²/8× 10⁻²× √ 10⁻² ( 8 + 5 )   N/C

Ey = 4623 N/C

To answer the second question again we will make use of symmetries if you look at drawing ( Figure 2 ) you see that again the components in direction of x-axis cancel each other and the components in y-axis direction will add. Then

Ey = ∫ dE× cosθ

following the same procedure  we will find:

Ey = ∫ [K×λ × dl/d²] × h/ d

The importan point here is that the radius of the circle is

2×π×r = 0.01      ( the length of the wire)  ⇒  r = 0.16×10⁻² m

And we need to take into account that the integration is over the circle and the length of the circle is 0.01 m or ××2×π×r. All other factors are constant. Then by substitution

Ey = [K×λ ×h×  / ( √ r² + h²)³ ] × 10⁻²    N/C

Ey = 8.9 × 10⁹ × 150× 10⁻⁹ × 6× 10⁻² × 10⁻² / √ 10⁻² ( 0.16 + 6)

Ey = 0.8 × 10² / 6

Ey = 19.34 N/C

Answer:

The number of electrons flowing per second is [tex]4.375\times 10^{18}[/tex].

Explanation:

How many electrons per second pass through a section of wire that carries a current of 0.70 A.?

Current, I = 0.7 A

time, t = 1 s

According to the definition of current, let the charge is q.

q = I t

q = 0.7 x 1 = 0.7 C

Let the number of electrons is n.

[tex]n =\frac{q}{e}\\\\n = \frac{0.7}{1.6\times 10^{-19}}\\\\n = 4.375\times 10^{18}[/tex]

Answer: prevent excitation light from reaching the detector

Explanation:

A fluorometer refers to the device that's used in the measurement of parameters that are of visible spectrum fluorescence. They also prevent excitation light from reaching the detector.

These parameters are used in the identification of the amount and presence of molecules in a medium.

Answer:

C. Increase in back emf

Explanation:

As the current through the field winding decreases the field strength also decreases and the back-emf is reduced, as a result the motor speeds up.

When the motor begins to speed-up, an additional back EMF is generated due to induction which reduces armature current. This also results in reduced strength of the field flux. The back emf generated is not enough to reduce the armature current which could stop the acceleration of the motor and the motor further accelerates.

Answer:

C. 9.9 cm

Explanation:

The location of the object, u = 14 cm

The location of the image, v = 5.8 cm

The focal length of the mirror, f = Required

The mirror formula for a convex mirror is given as follows;

[tex]\dfrac{1}{u} -\dfrac{1}{v} = -\dfrac{1}{f}[/tex]

Therefore, we get;

[tex]\dfrac{1}{14 \ cm} -\dfrac{1}{5.8 \ cm} =- \dfrac{41}{406 \ cm} = -\dfrac{1}{f}[/tex]

Therefore;

[tex]f = \dfrac{406 \ cm}{41} \approx 9.9 \ cm[/tex]

The focal length of the mirror, f ≈ 9.9 cm

Answer:

-29.9907

Explanation:

c = Q / (mΔT)

You're looking for ΔT, so you would plug in what you already know and get C= -12540/(100 x ΔT)

then you would solve

Answer: C- the outer core

Explanation: The outer core is a thick layer of molten rock that encircles the inner core.

Answer:

Its all about figuring out what numbers you times by

Explanation:

soooooooooo just x the numbers until you get it right, and i'm guessing your in a school soooo ask your teacher aswell :)

Answer:

I = 0.2 A

Explanation:

Lamp is rated at 300 mA

I_lamp = 300 mA = 0.3 A

Voltage is; V = 3V

Thus; Resistance is given by;

R = V/I

R = 3/0.3

R = 10 ohms

Now, since the ammeter of 5 ohms is connected in series with the lamp. Thus equivalent resistance;

R_eq = 10 + 5

R_eq = 15 ohms

Ammeter current will be;

I = V/R_eq

I = 3/15

I = 0.2 A

Answer:

Explanation:

First I converted the km/h to m/s, which is the more common unit for velocity. In m/s, 105 km/h is 29.2. Thus, to find the x component of the vector:

29.2cos25 = 26 m/s

If you want it in km/h:

105cos25 = 95 km/h

Answer:

I = sum m *r^2    where m represents the (small) individual masses and r is the distance of that mass from center of rotation

Note:  sum m = M

For the hoop given all masses are at a distance RRR from the center of rotation

I = MMM * RRR^2

Explanation:

Hydraulic Pressure-Control, On-Off Deluge Valve

FP-400Y-5DC

The BERMAD model 400Y-5DC is an elastomeric, hydraulic line pressure operated deluge valve, designed specifically for advanced fire protection systems and the latest industry standards. The 400Y-5DC is activated by a hydraulically operated relay valve, through which opening and closing of the valve can be controlled either with a remote hydraulic command or with a wet pilot line with closed fusible plugs. An integral pressure reducing pilot valve ensures a precise, stable, pre-set downstream water pressure. The optional valve position indicator can include a limit switch suitable for Fire & Gas monitoring systems. The 400Y-5DC is ideal for systems that combine a remote wet pilot line with a high pressure water supply.

Answer:

mechanical waves,

.

the quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone.

.

If the amplitude increases the volume increases and vice versa.

.

The type of medium affects a sound wave as sound travels with the help of the vibration in particles.

.

The higher the frequency, the shorter the wavelength.

Explanation:

Answer:

1 . Soundwave

2. pitch are sounds that are high or low corresponding and according to a certain frequency measured in Hertz

3. volume is the increase in sound or decrease in sound how loud or soft something is while amplitude is strength of sound

4. frequency is measured in Hertz one wave per second and wavelength is distance between corresponding points of two recurring and consecutive sound waves

Answer:

same value because both sides are equal

Explanation:

equal value

Answer:

Our weight on moon is less than it would be on Earth.

Explanation:

Due to a difference of the strength of gravity on the moon. The moon's gravitation force is determined by the mass and the size of the moon. Since the moon has significantly less mass than the Earth, it will not pull objects toward itself at the strength that Earth will. This means that if you went to the moon you would weigh less, even though your mass stays the same.

Such asSuch ToSuch aSuch as طHow do I send the answer to the question?OkI don't know how to use this program

Answer:

MOMENTUM = 40kg ms-¹

hope it helps

have a nice day

Answer:

0.2

Explanation:

The given parameters are;

The acceleration of the train, a = 0.2·g

The mass of the person standing on the train = m

Let μ represent the coefficient of static friction, we have;

The force acting on the person, F = m × a = m × 0.2·g

The force of friction acting between the feet and the floor, [tex]F_f[/tex] = m·g·μ

For the person not to slide we have;

The force acting on the person = The force of friction acting between the feet and the floor

F = [tex]F_f[/tex]

∴ m × 0.2·g = m·g·μ

From which we get;

0.2 = μ

The coefficient of static friction that must exist between the feet and the floor if the person is not to slide, μ = 0.2.

Answer:

2.9

Explanation:

es 2 minutos con 9 segundos seria algo así (1450)÷(500)

Answer:

Oort cloud

Explanation:

The large reservoir of comet nuclei far beyond Pluto, from which we believe new long-period comets come into the inner solar system, is called Oort cloud.

The comets hich have the large periods that means more than 200 years to orbit the Sun generaly comes from Oort cloud hich is also knon as the cometary cloud.

hope it is helpful to you

Answer:

A. to reduce the loss of energy in the form of heat across the transformer

Explanation:

The core of the transformer is laminated to minimise the energy as they interfere with the efficient transfer of energy from the primary coil to the secondary one. The eddy currents cause energy to be lost from the transformer as they heat up the core - meaning that electrical energy is being wasted as heat.

Answer:

6Eo

Explanation:

Answer:

65000g

24.325 hrs

7500m

Answer:

I) 65000 g   II)24.325 hours  III)7500 m

Explanation:

I) 1 kg = 1000 g

65 kg = 65 * 1000 g = 65000 g

II) 1 hour = 3600 seconds

1 second = 1/3600 hours

87570 seconds = 87570 * 1/3600 hours =24.325 hours

III) 1 km = 1000 m

7.5 km = 7.5 * 1000 m = 7500 m

Answer:

Look at work

Explanation:

Your given the mass of planet M and radius as well as second mass.

Use universal gravitation law to find force of gravity

Fg= Gm1m2/r^2

Plug in givens

Fg= 553.6 N

Use newtons second law

Fg= ma

553.6N=5a

solve for a= 110.72m/s

Weight is 553.6N

Answer:

More than two million electron volts.

Explanation:

More than two million electron volts energy are needed to break or split a deuteron into a proton and a neutron. Nuclear binding energy is the type of energy that is required to split an atom's nucleus into protons and neutrons. The deuteron is an isotope of hydrogen that is composed of a proton and a neutron and it is a stable particle. Very huge amount of energy is needed for the splitting of nucleus due to the presence of heavy particles i.e. proton and neutron.

Answer:

Acceleration is 1.2 m/s^2.

Explanation:

initial velocity, u = 0

distance, d = 60 m

time, t = 10 s  

Let the acceleration is a.

use second equation of motion

[tex]s= u t +0.5 at^2\\\\60 = 0 + 0.5 \times a \times 10\times 10\\\\a = 1.2 m/s^2[/tex]

Now according to the Newton's second law

Force = mass x acceleration

Let the mass is m.

F = m x 1.2 = 1.2 m Newton  

Answer:

[tex]t = \frac{\pi}{8}, \frac{\pi}{4}, \frac{3\pi}{8}, \frac{3 \pi}{4}[/tex]

Explanation:

The equation of force is

F = 4 sin 4 t

Compare with the standard equation

f = A sin wt

where, w is the angular frequency and A is the amplitude.

Now

w = 4 rad/s

Let the time period is T.

the relation for the time period is

[tex]T = \frac{2\pi}{w}\\\\T = \frac{2 \pi}{4}\\\\T = \frac{\pi}{2}[/tex]

the time period is defined as the time taken by the body to complete one oscillation.

So, the velocity is zero at the extreme points where the object is at time, T/4 and its odd T/2, 3T/4, 3T/2, etc.

So, the velocity is zero at time

[tex]t = \frac{\pi}{8}, \frac{\pi}{4}, \frac{3\pi}{8}, \frac{3 \pi}{4}[/tex]

Answer:

1-The liquid pressure is same at all points lying on the same horizontal plane in a stationary liquid.

2-The liquid pressure at a point inside the liquid is same in all directions.

3-The liquid pressure at a point inside the liquid is directly proportional to the depth of that point from the free surface of liquid.

4-The pressure of liquid at same depth is different for different liquids. It is directly proportional to density of liquid. That is, for same depth the liquid pressure is larger for liquid of larger density.

Explanation: