Explanation:
10 Reasons to Look Forward to GoingBack to School..
The people. ... The places. ... The events. ... Extracurricular activities. ... The dining plan options. ... The housing options. ... The freedom. ... The first day of classes.You are making photoelectric measurements on an electrode of an unknown metal. With zero potential difference applied by the battery, you shine various freqencies of light on the cathode. You detect a small photocurrent for light with wavelength up to 451 nm. What metal is the electrode made of
Since you detect a small photocurrent for light with wavelength up to 451 nm, the metal the electrode is made of is Sodium.
To solve the question, we need to know what work function is.
What is work function of a metal?This is the minimum energy at which an electron will be emitted from the surface of a metal.
Since a small photocurrent is detected when ligh of wavelength up to 451 nm is applied with a zero potential difference applied, this is the threshold wavelength which gives the work function of the metal.
So, work function Ф = hc/λ where
h = Planck's constant = 6.63 × 10⁻³⁴ Js, c = speed of light = 3 × 10⁸ m/s and λ = wavelength of light = 451 nm = 451 × 10⁻⁹ mSubstituting the values of the variables into the equation, we have
Ф = hc/λ
Ф = 6.63 × 10⁻³⁴ Js × 3 × 10⁸ m/s ÷ 451 × 10⁻⁹ m
Ф = 19.89 × 10⁻³⁴ × 10⁸ Jm ÷ 451 × 10⁻⁹ m
Ф = 0.0441 × 10⁻¹⁷ J
Ф = 4.41 × 10⁻¹⁹ J
Since 1 eV = 1.602 10⁻¹⁹ J,
Ф = 4.41 × 10⁻¹⁹ J × 1 eV/1.602 10⁻¹⁹ J
Ф = 2.753 eV
From tables, the metal with the work function closet to this value is Sodium.
So, the metal the electrode is made of is Sodium.
Learn more about work function of metal here:
https://brainly.com/question/13030285
find the work done by the engine of a car which moves at an acceleration of 3 m / s2 for 8s. the mass of the car is 1400 kg, while the coefficient of fecundation of its wheels with the road is 0.03.
Explanation:
so that u multiple in this formula
Answer:
362.88 kJExplanation:
Given
a = 3 m/s²t = 8 sm = 1400 kgμ(k) = 0.03Finding Displacement
S = ut + 1/2at²S = 0 + 1/2(3)(8)²S = 32(3) = 96 mFinding Net Force
Applied Force (F) = ma = 1400 x 3 = 4200 NFriction Force (f) = μmg = 0.03 x 1400 x 10 = 420 NNet Force = F - f = 4200 - 420 = 3780 NWork Done
W = FS = 3780 N x 96 mW = 362880 JW = 362.88 kJWhich formula can be used to solve problems related to the first law of thermodynamics? q = w u q = u – deltaw q = u w q = u – w
"Q = ΔU + W" is the equation is used to solve the questions related to "First law of thermodynamics".
What is the first law of thermodyanamics?"First law of thermodynamics" states that "energy" neither created nor destroyed, but it can transfer from "one form of energy" to "another form of energy".
This "First law of thermodynamics" is also called as "law of conversation of energy". The formula for "First law of thermodynamics" of a system is that "change in internal energy of a system" is same as the difference of "heat energy" flows across the " boundaries of a system" and the "work done" on the system.
ΔU = Q - W
Q = ΔU + W
Where, "ΔU" is "change in internal energy", "Q" is "heat transferred and "W" is "work done.
Hence "Q = ΔU + W" is the equation is used to solve the questions related to "First law of thermodynamics".
To know more about the First law of thermodynamics follow
https://brainly.com/question/15071682
A footballer kicks a football of mass 430 g and it flies off at a speed of 8 m/s. What is the KE of the football?
Answer:
13.76 Joules
Explanation:
The SI units for joules are defined to be kilogram*meters per second. Therefore, we must turn the grams to kilograms by dividing the answer by 1,000. This is due to 1,000 grams being in a single kilogram. Kinetic energy is defined to be:
[tex]KE=\frac{1}{2} mv^2[/tex]
Therefore:
[tex]KE=\frac{1}{2} (0.43kg)(8m/s)^2=13.76J[/tex]
A disk with radius of 0. 5 m is free to rotate around its center without friction. A string wrapped around the disk is pulled, as shown above, exerting a 2 n force tangent to the edge of the disk for 1 s. If the disk starts from rest, what is its angular speed after 1 s?.
For a disk with radius of 0. 5 m is free to rotate around its center without friction, its angular speed after 1 s is mathematically given as
w=1/(0.5M π^2)
What is its angular speed after 1 s?Generally, the equation for the Moment of inertia is mathematically given as
I=0.5mx^2
Where
radius = 0. 5 m
Mass=M
Force on edge=F=2N
Time =t
Hence, Torque
T=0.5*2=1.0Nm
Where
T=Ia
w=W0+at
Hence
W=1/I
In conclusion, angular speed after 1 s
I=0.5M π^2
w=1/(0.5M π^2)
Read more about Speed
https://brainly.com/question/4931057
#SPJ1
What is the relationship between frequency and wavelength?
Answer:
Frequency and wavelength are inversely proportional to each other. The wave with the greatest frequency has the shortest wavelength. Twice the frequency means one-half the wavelength.
Explanation:
9. As a cold front passes a New York weather station,
which changes will usually be observed in barometric
pressure and air temperature?
A) Pressure rises and temperature falls.
B) Both pressure and temperature rise.
C) Both pressure and temperature fall.
D) Pressure falls and temperature rises.
When the cold front or wind passes weather station, the pressure increases whereas the temperature increases.
What happen when cold front passes a New York weather station?Pressure rises and temperature falls as a cold front passes a New York weather station because wind apply pressure on the objects when they blow. If the wind is cold then the temperature decreases.
So we can conclude that when the cold front or wind passes weather station, the pressure increases whereas the temperature increases.
Learn more about pressure here: https://brainly.com/question/25736513
#SP1
What is the difference between synchronous and asynchronous?.
Answer:synchronous communications are scheduled, real-time interactions by phone, video, or in-person. Asynchronous communication happens on your own time and doesn't need scheduling.
Explanation:
Which element is more likely to give up electrons than to gain them during a reaction? A.fluorine b.boxygen c.carbon d.lithium
Answer:
Lithium
Explanation:
Elements that are metals are tend to lose electrons and become positively charged ions called Cations. Elements that are non metals tend to gain electron and become negatively charged ions called Anions.
Three examples of good hypotheticals
Answer:
here are some of my favorites
Explanation:
if the world was ending, what would you do?
if you had super powers. what would they be?
if we could go to the moon, would you?
Answer:
If Life was a human, how would you treat him/her?If death was a god would you praise him?And If wishes were dead, would you bring them back alive?Explanation:
{horrifically chuckles]
*Leaves the room*
A go-cart is rolling down a hill at 15m/s. If it has 85J of kinetic energy. what is the mass of the go-cart?
0.76kg
0.87kg
5.67kg
0.18kg
Which sound wave has higher pitch
Can you also compare the loudness of both
Answer:
Below one has higher pitchLoudness is roughly the sameExplanation:
Pitch depends on frequencyThe below one has a higher frequency, hence it has a higher pitchThe loudness depends on the amplitudeThe amplitude here in the two is roughly the same as the height of the waves are similarA ray of light passing through centre of curvature of a concave mirror is incident on its reflecting surface. What is the angle of incidence and reflection of this ray of light?
8TH GRADE SCIENCE PLEASE HELPPP
Answer:
The two helicopters have the same kinetic energy, but a different GPE, or gravitational potential energy.
Explanation:
A weightlifter holds a barbell motionless at her chest as she prepares to lift it over her head. The work done by the weightlifter to hold the barbell in this position is
Answer:
it's a bit of a trick question
Explanation:
W = distance X force
when the distance is zero, the work is zero. So when she holds the weight without moving them she is doing no work. But, to be fair, that's just the wording, what "work" means. she is actually producing a force, that is equal to the weight of the barbells, to hold them against the graviational force.
a sound is first produced by making something BLANK the sound then travels through a BLANK to reach the ears, which are the parts of the body that allow for sounds to be heard
Answer:
vibrate, medium.
Explanation:
Edge, 2022.
A system is heated with 134 J of energy and, at the same time, the system expands, doing 89 J of work. What is the change in internal energy of the system, in Joules
The change in internal energy of the system after the heat is added and the system expands doing work to the surrounding is 45 J.
Change in internal energy of the system
The change in internal energy of the system is determined by applying the first law of thermodynamics as shown below;
ΔU = q - w
where;
ΔU is the change in the internal energyq is heat added to the systemw is work done to the surroundingsΔU = 134 J - 89 J
ΔU = 45 J
Thus, the change in internal energy of the system after the heat is added and the system expands doing work to the surrounding is 45 J.
Learn more about change in internal energy here: https://brainly.com/question/23236669
In straight line path, magnitude of velocity is equal to
Acceleration
Explanation:
The particle is moving in a straight line. That means there’s no change in the path of the particle in the entire trip. It is moving with constant acceleration, meaning the particle doesn’t change its acceleration at all. The acceleration direction is in the same direction of instantaneous velocity
Which space mission visited the moon several times?.
Unpolarized light of intensity Io is incident on a stack of 7 polarizing filters, each with its axis rotated 17°cw with respect to the previous filter. Find the ratio between light intensity emerges from the last filter and unpolarized light of intensity Io. It/Io= _________
The ratio of the intensity between light intensity that emerges from the last filter and unpolarized light of intensity, I₀ is It/I₀ = 0.2925
To answer the question, we need to know what polarization of light is.
What is polarization of light?This is when the electric field vector of light is oscillating in one plane.
Now for light of intensity I' which is initially unpolarized, its intensity after polarization is I = 1/2I'.Also, for light initially polarized, its intensity after polarization is I"' = I"cos²Ф where Ф is the angle between the initial direction and the direction of polarization.Intensity of light through each polarized filterGiven that we have 7 polarizing filters, each rotated 17° cw with respect to the previous filter.
So, since the light is initially unpolarized,
The intensity through the first polarizing filter is I₁ = 1/2I₀ where I₀ is the initial intensity.The intensity through the second polarizing filter is I₂ = I₁cos²17°= 1/2I₀cos²17°The intensity through the third polarizing filter is I₃ = I₂cos²17° = 1/2I₀cos⁴17°The intensity through the fourth polarizing filter is I₄ = I₃cos²17° = 1/2I₀cos⁶17°The intensity through the fifth polarizing filter is I₅ = I₄cos²17° = 1/2I₀cos⁸17°The intensity through the sixth polarizing filter is I₆ = I₅cos²17° = 1/2I₀cos¹⁰17°The intensity through the seventh polarizing filter is I₇ = I₆cos²17° = 1/2I₀cos¹²17°.The ratio of the intensity between light intensity that emerges from the last filter and unpolarized light of intensitySince I₇ is the last intensity I₇ = It = 1/2I₀cos¹²17°.
So, It/I₀ = 1/2cos¹²17°
= 1/2(0.9563)¹²
= 1/2 × 0.5850
= 0.2925
So, the ratio of the intensity between light intensity that emerges from the last filter and unpolarized light of intensity, I₀ is It/I₀ = 0.2925
Learn more about intensity of polarized light here:
https://brainly.com/question/25402491
Examine the distance-time graph.
Which line represents travel at the fastest speed? Justify your answer.
Answer:
A
Explanation:
because it is accelerating and as the vehicle accelerates the speed increas
When the reflection of an object is seen in a flat mirror, the image is.
Answer:
the image is actually appearing behind the mirror, and not in the mirror.
Which are thought to have formed farthest from the sun?.
What is the net force that acts on a 5 kg object accelerating at 2m/s
Answer:
10 N
Explanation:
I assume there is no friction and we are only worrying about the horizontal direction. If so we use the formula F=MA to get F= 2 * 5 = 10 N
PLEASE ANSWER QUICKLY
Answer:
the third one
Explanation:because coal cause more pollition
Energy is the capacity to do work or
produce a change. Energy of position is
called potential energy. Energy of motion
is called kinetic energy.
Which situation best illustrates potential
energy being converted into kinetic
energy?
(1) a baseball landing on the ground
(2) a car coming around a corner
(3) turning off an electric lamp
(4) an apple falling from an apple tree
(5) a jogger running in a race
Answer:
4
Explanation:
Apple initially has Potential energy due to it's height and mass
as it falls this PE is converted to KE
An apple falling from an apple tree illustrates potential energy being converted into kinetic energy. So, the correct option is (D).
What is Potential and Kinetic Energy?Kinetic energy is a type of energy which is possessed by an object due to its motion while Potential energy is the type of energy possessed by an object due to its position or state.
While kinetic energy is relative to the position of other objects in its environment, potential energy is completely independent of its environment.
Kinetic energy can be transferred from one moving object to another while potential energy cannot be transferred. The formula of Kinetic energy is [tex]1/2 mv^2[/tex] while the formula of Potential energy is mgh where m is the mass, v is the velocity, h is the height of an object and g is the acceleration due to gravity. S.I. unit of both is Joules (J). In the given information, the apple which is on the tree is in rest mode i.e. potential energy falls from the tree, changing its motion i.e. kinetic energy.
Thus, an apple falling from an apple tree illustrates potential energy being converted into kinetic energy. So, the correct option is (D).
Learn more about Kinetic and Potential energy, here:
https://brainly.com/question/15764612
#SPJ2
Which describe the image formed by the convex
mirror? Check all that apply.
-real
-virtual
-inverted
-upright
-smaller
-larger
Answer:
- Virtual
- Upright
- Smaller
Explanation:
I just did it on Edg22 and I got it correct :D
Answer:
see the picture
Explanation:
a toy airplane takes off and flies for a distance of 34 meters at an angle of 26 degrees above the horizontal. what is its altitude when it has flown this distance?
Answer:
Explanation:
14.9m
The altitude when the airplane flies a distance of 34 m is equal to 14.9 m.
What is the distance?The distance of an object can be demonstrated as the total length traveled by an object. The distance can be defined as a scalar parameter as it has magnitude, not direction. The distance by an object is always positive (+ve), it can never be zero.
Given, the airplane traveled the distance, BC = 34m as shown in the attached diagram, below:
The angle of the path with horizontal, θ = 26°
From the right angle triangle ΔCBA, we can calculate the BC:
Sin θ = BC/AC
Sin 26° = x/34
x = sin 26° ×34
x = 0.438 × 34
x = 14.9 m
Therefore, the altitude when an airplane has flown this distance is 14.9 m.
Learn more about distance, here:
brainly.com/question/3243551
#SPJ2
All masses cannot be measured in kilogram, why ?
Answer:
We cannot measure all masses in kg, because there are very small quantities like 1gm nd even smaller, and this will not be an accurate measurement in Kg.
What is the appropriate distance for social space?.
Answer:
Social distance ranges from 4 to 8 feet (1.2 m - 2.4 m) away from the person and is reserved for strangers, newly formed groups, and new acquaintances. Neuropsychology describes personal space in terms of the kinds of 'near-ness' to the body. 1.