When light with a wavelength of 221 nm is incident on a certain metal surface, electrons are ejected with a maximum kinetic energy of J. Determine the wavelength of light that should be used to double the maximum kinetic energy of the electrons ejected from this surface

Answer:

36 times less.

Explanation:

The distance from you to the sun is 6AU's, and from the sun to the earth is 1 AU.

Therefore,

At Earth sunlight received per unit cm² is:

[tex]I_{earth} = \dfrac{I_o}{4 \pi \times (1)^2}[/tex]

[tex]I_{earth} = \dfrac{I_o}{4 \pi}[/tex]

[tex]I_{me} =\dfrac{I}{4 \pi (6)^2}[/tex]

[tex]I_{me} = \dfrac{I_o}{36(4 \pi)}[/tex]

Thus, [tex]I_{earth} = 36 \times I_{me}[/tex]

Thus, the right answer is 36 times less.

Answer:

a. Speed = 1.6 m/s

b. Amplitude = 0.3 m

c. Speed = 1.6 m/s

Amplitude = 0.15 m

Explanation:

a.

The frequency of the wave must be equal to the reciprocal of the time taken by the boat to move from the highest point to the highest point again. This time will be twice the value of the time taken to travel from the highest point to the lowest point:

frequency = [tex]\frac{1}{2(2\ s)}[/tex] = 0.25 Hz

The wavelength of the wave is the distance between consecutive crests of wave. Therefore,

Wavelength = 6.4 m

Now, the speed of the wave is given as:

Speed = (Frequency)(Wavelength)

Speed = (0.25 Hz)(6.4 m)

Speed = 1.6 m/s

b.

Amplitude is the distance between the mean position of the wave and the extreme position. Hence, it will be half the distance between the highest and lowest point:

Amplitude = (0.5)(0.6 m)

Amplitude = 0.3 m

c.

frequency = [tex]\frac{1}{2(2\ s)}[/tex] = 0.25 Hz

Speed = (Frequency)(Wavelength)

Speed = (0.25 Hz)(6.4 m)

Speed = 1.6 m/s

Amplitude = (0.5)(0.3 m)

Amplitude = 0.15 m

Answer:

I think it's light year but there shouldn't be also km/s but km/h

Answer:

Ability of the Keck telescope to capture more distant object despite been atop Mauna kea that Hale Telescope may not capture even if it is atop Palomar mountain in California

Explanation:

If increasing the Diameter of a Telescope beyond a given value will increase the ability of the telescope to capture more light and also capture astronomical objects located in a very distant position without improving resolution.

Hence the superiority of Keck telescope atop Mauna Kea over Hale Telescope atop Palomar mountain in California is the ability of the Keck telescope to capture more distant object despite been atop Mauna kea that Hale Telescope may not capture even if it is atop Palomar mountain in California

Answer:

390 light-years

Explanation:

50 x 7.8 =390

Answer:

Explanation:

Option C is the correct answer

Some thermometers contain alcohol. Alcohol is used in thermometers because expands and contracts easily. The correct option is C.

Thermometer is the temperature measuring device which consists of a liquid in the bulb which expands as the temperature is increased.

The liquid metal used in the thermometer must have the property to respond on the hotness and coldness rapidly.

In place of mercury, some thermometers use alcohol because an alcohol has a very low freezing point as compared to the Mercury.

Thus, the correct option is C.

Learn more about thermometers.

https://brainly.com/question/24189042

#SPJ2

Some thermometers contain alcohol. Alcohol is used in thermometers because expands and contracts easily.

Answer:

Explanation:

any more explanation?

Answer:

the answer is D I tought

Answer:

B.

Divide the height of the valley walls by the rate of erosion.

Explanation:

There is a relationship between the rate of erosion and the hieght at which it is eroded according to Newton's law of motion. In the case of the scenario above, the best way to determine the time the river started carving the valley would be the division of the height of the valley walls by the rate of erosion.

Answer:

a) Battery-operated devices have: small led lights, flashlights, wireless keyboards and mice, watches, electronic weights

b) ed lights and flashlights transform into light energy and thermal energy

c)  Em₀ = U = m gh,  Em_f = K = ½ m v²

Explanation:

In this exercise ask to complete the sentences

a) Battery-operated devices have: small led lights, flashlights, wireless keyboards and mice, watches, electronic weights

b) These devices transform the chemical energy stored in the batteries into other forms of energy.

Led lights and flashlights transform into light energy and thermal energy

Keyboards transform into electromagnetic energy that is emitted

clocks transform to mechanical energy from the movement of the needles

Electronic weights transforms the chemical energy of the baria into gravitational potential energy that prevents the movement of the plate and this translates into the reading of the body weight

c) The total energy of the cylinder mechanical energy when sustained is

          Em₀ = U = m gh

it is transformed as it descends into kinetic energy, at any point

          Emₙ = K + U = 1/2 m v² + m g y

at the lowest point of the trajectory all energy is transformed

           Em_f = K = ½ m v²

Answer:

right

Explanation:

Answer:

so you have a question

Explanation:

either way, have a nice day

Answer:

Explanation:

iphotosynthesis 2coal burning 3electric motor 4 electricity generator 5 waterturbines 6 solar bulb

Answer:

The total linear acceleration is approximately 0.246 meters per square second.

Explanation:

The total linear acceleration ([tex]a[/tex]) consist in two components, radial ([tex]a_{r}[/tex]) and tangential ([tex]a_{t}[/tex]), in meters per square second:

[tex]a_{r} = \omega^{2}\cdot r[/tex] (1)

[tex]a_{t} = \alpha \cdot r[/tex] (2)

Since both components are orthogonal to each other, the total linear acceleration is determined by Pythagorean Theorem:

[tex]a = \sqrt{a_{r}^{2}+a_{t}^{2}}[/tex] (3)

Where:

[tex]r[/tex] - Radius of the wheel, in meters.

[tex]\omega[/tex] - Angular speed, in radians per second.

[tex]\alpha[/tex] - Angular acceleration, in radians per square second.

Given that wheel accelerates uniformly, we use the following kinematic equation:

[tex]\omega = \omega_{o}+ \alpha\cdot t[/tex] (4)

Where:

[tex]\omega_{o}[/tex] - Initial angular speed, in radians per second.

[tex]t[/tex] - Time, in seconds.

If we know that [tex]r = 0.1\,m[/tex], [tex]\alpha = 2\,\frac{rad}{s^{2}}[/tex], [tex]\omega_{o} = 0\,\frac{rad}{s}[/tex] and [tex]t = 0.60\,s[/tex], then the total linear acceleration is:

[tex]\omega = \omega_{o}+ \alpha\cdot t[/tex]

[tex]\omega = 1.2\,\frac{rad}{s}[/tex]

[tex]a_{r} = \omega^{2}\cdot r[/tex]

[tex]a_{r} = 0.144\,\frac{m}{s^{2}}[/tex]

[tex]a_{t} = \alpha \cdot r[/tex]

[tex]a_{t} = 0.2\,\frac{m}{s^{2}}[/tex]

[tex]a = \sqrt{a_{r}^{2}+a_{t}^{2}}[/tex]

[tex]a \approx 0.246\,\frac{m}{s^{2}}[/tex]

The total linear acceleration is approximately 0.246 meters per square second.

Answer:

Surface tension is,  the surface where the water meets the air, water molecules cling even more tightly to each other.

Answer:

what

you need to elaborate

Answer: Can you please write question clearly.

Explanation:

Answer:

FATS

Explanation:

Fats are made up of carbon and hydrogen elements joined together in long groups called hydrocarbons. The simplest unit of fat is the fatty acid, of which there are two types: saturated and unsaturated.

The macronutrient which is made up of carbon and hydrogen elements joined together in long groups called hydrocarbons is: D. Fats​.

A macronutrient refers to a very large molecule (structure) that comprises covalently bonded organic atoms (hydrocarbons) and smaller molecular structures (monomers).

In Science, macronutrients are grouped into four (4) main categories and these are;

Fats (Lipids) are macronutrients that are typically made up of both carbon and hydrogen elements, which are joined together in long groups referred to as hydrocarbons.

Find more information: https://brainly.com/question/14681125

Answer:

I = 0.65 kgm²

Explanation:

Since the mass is an inertial pendulum, we use the formula for the period, T of an inertial pendulum.

T = 2π√(I/mgh) where I = moment of inertia of object about pivot point, m = mass of object5 = 4.07 kg, g = acceleration due to gravity = 9.8 m/s² and h = distance of center of mass of object from pivot point = 0.155 m.

Given that the team measures 113 cycles of oscillation in 247 s, the period, T = time of oscillations/total number of oscillations = 247 s/113 oscillations = 2.186 s/oscillation

So, T = 2.186 s

We now find I by making it subject of the formula in the equation for T.

So,

T = 2π√(I/mgh)

dividing both sides by 2π, we have

T/2π = √(I/mgh)

squaring both sides, we have

(T/2π)² = [√(I/mgh)]²

T²/4π² = I/mgh

multiplying both sides by mgh, we have

T²mgh/4π² = I

I = T²mgh/4π²

substituting the values of the variables into the equation, we have

I = T²mgh/4π²

I = (2.186 s)² × 4.07 kg × 9.8 m/s² × 0.155 m/4π²

I = 4.778 s² × 4.07 kg × 9.8 m/s² × 0.155 m/4π²

I =  29.539 kgm²/4π²

I = 0.748 kgm²

Now I = I' + mh²  (parallel axis theorem) where I' = moment of inertia of object about its center of mass, m = mass of object = 4.07 kg and h = distance of center of mass object from pivot point.

So, I' = I - mh²

Substituting the values of the variables into the equation, we have

I' = I - mh²

I' = 0.748 kgm² - 4.07 kg × (0.155 m)²

I' = 0.748 kgm² - 4.07 kg × 0.02403 m²

I' = 0.748 kgm² - 0.098 kgm²

I = 0.65 kgm²

Answer:

a)[tex]\frac{F_1}{L}=1.95*10^-^5N[/tex]

b)[tex]\frac{F_2}{L}=1.95*10^-^5N[/tex]

Explanation:

From the question we are told that:

Distance between wires [tex]d=32.2[/tex]

Wire 1 current [tex]I_1=2.75[/tex]

Wire 2 current [tex]I_2=4.33[/tex]

a)

Generally the equation for Force on [tex]l_1[/tex] due to [tex]I_2[/tex] is mathematically given by

[tex]F_1=I_1B_2L[/tex]

Where

B_2=Magnetic field current by [tex]I_2[/tex]

[tex]B_2=\frac{\mu *i_2}{2\pi d}[/tex]

Therefore

[tex]F_1=I_1B_2L[/tex]

[tex]F_1=I_1(\frac{\mu *i_2*l_1}{2\pi d})L[/tex]

[tex]\frac{F_1}{L} =\frac{4*\pi*10^{-7}*2.75*4.33*100 }{2*\pi*12.2 }[/tex]

[tex]\frac{F_1}{L}=1.95*10^-^5N[/tex]

b)

Generally the equation for Force on [tex]I_2[/tex] due to [tex]I_1[/tex] is mathematically given by

[tex]F_2=I_2B_1L[/tex]

Where

B_1=Magnetic field current by [tex]I_2[/tex]

[tex]B_1=\frac{\mu *I_1}{2\pi d}[/tex]

Therefore

[tex]\frac{F_2}{L} =I_2(\frac{\mu *I_1*I_2}{2\pi d})[/tex]

[tex]\frac{F_2}{L}=1.95*10^-^5N[/tex]

Answer:

a) number of copper atoms 65 (⁶⁵Cu)  is 7.692 10⁶ atoms

b) m_total Cu = 1.585 10⁹ u = 2.632 10⁻¹⁸ kg

Explanation:

a) For this exercise let's start by using the radioactive decay ratio

           N = N₀  [tex]e^{- \lambda t}[/tex]o e - lambda t

The half-life time is defined as the time it takes for half of the radioactive (activated) atoms to decay, therefore after two half-lives there are

            N = ½ (½ N₀) = ¼ N₀

            N₀ = 4 N

in each decay a photon is emitted so we can use a direct rule of proportions. If an atom emits a photon it has Eo = 1,04 Mev, how many photons it has energy E = 10,000 MeV

          # _atoms = 1 atom (photon) (E / Eo)

          # _atoms = 1 10000 / 1.04

          # _atoms = 9615,4 atoms

          N₀ = 4 #_atoms

          N₀ = 4 9615,4

          N₀=  38461.6  atoms

in the exercise indicates that half of the atoms decay in this way and the other half decays directly to the base state of Zinc, so the total number of activated atoms

          N_activated = 2 # _atoms

          N_activated = 2 38461.6

          N_activated = 76923.2

also indicates that 1% = 0.01 of the nuclei is activated by neutron bombardment

          N_activated = 0.01 N_total

          N_total = N_activated / 0.01

          N_total = 76923.2 / 100

          N_total = 7.692 10⁶ atoms

so the number of copper atoms 65 (⁶⁵Cu)  is 7.692 10⁶

b) the natural abundance of copper is

  ⁶³Cu     69.17%

  ⁶⁵Cu    30.83%

Let's use a direct proportion rule. If there are 7.692 10⁶  ⁶⁵Cu that represents 30.83, how much ⁶³Cu is there that represents 69.17%

                # _63Cu = 69.17%  (7.692 10⁶    / 30.83%)

                # _63Cu = 17.258 10⁶  atom  ⁶³Cu

the total amount of comatose is

              #_total Cu = #_ 65Cu + # _63Cu

              #_total Cu = (7.692 + 17.258) 10⁶

              #_total Cu = 24.95 10⁶

the atomic mass of copper is m_Cu = 63.546 u

          m_total = #_totalCu m_Cu

          m_total = 24.95 10⁶ 63,546 u

          m_total = 1.585 10⁹ u

let's reduce to kg

           m_total Cu = 1.585 10⁹ u (1,66054 10⁻²⁷ kg / 1 u)

           m_total Cu = 2.632 10⁻¹⁸ kg

Answer:

Explanation:

The answer is a priest or a moulana

Answer:

the ratio of her final kinetic energy to her initial kinetic energy is 1.7.

Explanation:

Given;

initial angular speed, ω₁ = 5.9 rad/s

let her initial moment of inertia = I₁

her final moment of inertia [tex]I_2 = \frac{I_1}{1.7}[/tex]

Apply the principle of conservation of angular momentum to determine the final angular speed of the girl;

[tex]\omega_1I_1 = \omega_f I_2\\\\\omega_f = \frac{\omega _1 I_1}{I_2} \\\\\omega_f = \frac{5.9 \times I_1}{I_1/1.7} \\\\\omega = 5.9 \times 1.7 \\\\\omega_f = 10.03 \ rad/s[/tex]

The initial rotational kinetic energy is given as;

[tex]K.E_I = \frac{1}{2}I_1 \omega_I ^2[/tex]

The final rotational kinetic energy is given as;

[tex]K.E_f = \frac{1}{2}I_2 \omega_f ^2[/tex]

The ratio of her final kinetic energy to her initial kinetic energy is given as;

[tex]\frac{K.E_f}{K.E_I}= \frac{\frac{1}{2}I_2 \omega_f^2 }{\frac{1}{2} I_1\omega _1^2} \\\\\frac{K.E_f}{K.E_I}= \frac{I_2 \omega_f^2}{ I_1\omega _1^2} \\\\\frac{K.E_f}{K.E_I}= \frac{I_1/1.7 \times \omega_f^2}{ I_1 \times \omega _1^2} \\\\\frac{K.E_f}{K.E_I}= \frac{ \omega_f^2}{ 1.7 \omega _1^2} \\\\\frac{K.E_f}{K.E_I}= \frac{ (10.03)^2}{ 1.7(5.9)^2} = \frac{17}{10} = 1.7[/tex]

Therefore, the ratio of her final kinetic energy to her initial kinetic energy is 1.7.

Answer:

i dont know  man

Explanation:

i dont know man

Answer: A (first option)

Explanation: In general, the surface temperatures decreases with increasing distance from the sun. Any warm object in space loses heat via infrared radiation; also visible radiation if it is hot enough. The hotter is the object, the faster it loses heat. Consequently any object warmed by the Sun stays at equilibrium temperature - it warms up until the radiative heat loss equals to the heat received, and cannot get any warmer beyond that.

Answer:

your answer gonna be The letter C is the correct answer

Answer:

Carbon dioxide controls the amount of water vapor in the atmosphere and thus the size of the greenhouse effect. Rising carbon dioxide concentrations are already causing the planet to heat up

Explanation:

Hope it helps! Correct me if I am wrong

Im sure about my answer

Answer:

35,000 km = 35,000,000 m = 3.5 E107 m

t = S / v = 3.5 * 10E7 / 3.0 E10E8 = .117 sec

Answer: D. An AC circuit

Explanation:

I took it on a test and it was correct ; )