Answer:
Work Function = 3.53 x 10⁻¹⁹ J = 2.2 eV
Explanation:
The work function of the metal metal can be found as follows:
Energy of Photon = Work Function + K.E
hc/λ = Work Function + K.E
Work Function = hc/λ - K.E
where,
h = Plank's Constant = 6.625 x 10⁻³⁴ J.s
c = speed of light = 3 x 10⁸ m/s
λ = wavelength of photons = 240 nm = 2.4 x 10⁻⁷ m
K.E = Maximum Kinetic Energy = (2.97 eV)(1.6 x 10⁻¹⁹ J/1 eV) = 4.752 x 10⁻¹⁹ J
Therefore,
Work Function = (6.625 x 10⁻³⁴ J.s)(3 x 10⁸ m/s)/(2.4 x 10⁻⁷ m) - 4.752 x 10⁻¹⁹ J
Work Function = 8.281 x 10⁻¹⁹ J - 4.752 x 10⁻¹⁹ J
Work Function = 3.53 x 10⁻¹⁹ J = 2.2 eV
A hydrogen atom in an excited state absorbs a photon of wavelength 411 nm. What were the initial and final states of the hydrogen atom?
Answer:
The initial and final states of the hydrogen atom were n=2 and n=6 respectively.
Explanation:
We must first obtain the energy of the photon;
E= hc/λ
where;
h= Plank's constant = 6.6 * 10^-34 JS
c= speed of light = 3* 10^8 m/s
λ = wavelength of light= 411 nm = 411* 10^-9 m
Substituting values;
E = 6.6 * 10^-34 * 3* 10^8 / 411* 10^-9
E = 4.8 * 10^-19 J or 3.0 eV
But ;
En = 13.6/n^2
So E = En final - En initial
3.0 = -13.6(1/n^2final - 1/n^2initial)
If we substitute n^2final = 6 and n^2 initial = 2 then the RHS becomes approximately equal to the LHS
Therefore the initial and final states of the hydrogen atom were n=2 and n=6 respectively.
why it is important to take care of our body?
Answer:
You need to care for the body to stay fit, healthy and clean.
When a skateboarder comes to a stop at the top of either side of a ramp, what happens to the potential and kinetic energy?
Answer:
potential is at maximum
kinetic energy is zero
A major artery with a 1.7 cm2 cross-sectional area branches into 18 smaller arteries, each with an average cross-sectional area of 0.4 cm2. By what factor is the average velocity of the blood reduced when it passes into these branches
Answer:
0.14
Explanation:
Flow rate is the volume flowing through a point at a particular time, in calcuing flow rate we have
Q= v*t
it in terms of Area, we have Q= A*v
Where A= area
v= velocity.
Solving the question , flow rate is constant then
A*v= constant
A(i) v(i)= A(f) v(f)
Where A(i)= initial area= 1.00cm^2
A(f)= final area= 0.400cm^2
V(i) and V(f) are the initial and final velocity respectively and the ratio of the two will gives us the factor
Substitute the values into the equation we have
1 V(i)= 4 V(f)
But we were told that the cross sectional area of 1.00cm^2 branches into 18 smaller arteries.
Then
1 V(i)=0.4 V(f)*(18)
1 V(i)=7.2V(f)
Then if we find the ratio of the velocity, we will get the factor.
V(f)/V(i)= 1/7.2
V(f)/V(i)=0.14
Hence, the factor of the average velocity of the blood reduced when it passes into these branches is 0.14
A bug crawled 35 meters in 20 seconds. What was the bugs velocity ?
(EXPLAIN)
If each of the three rotor helicopter blades is 3.50 m long and has a mass of 120 kg , calculate the moment of inertia of the three rotor blades about the axis of rotation.
Answer:
1470kgm²
Explanation:
The formula for expressing the moment of inertial is expressed as;
I = 1/3mr²
m is the mass of the body
r is the radius
Since there are three rotor blades, the moment of inertia will be;
I = 3(1/3mr²)
I = mr²
Given
m = 120kg
r = 3.50m
Required
Moment of inertia
Substitute the given values and get I
I = 120(3.50)²
I = 120(12.25)
I = 1470kgm²
Hence the moment of inertial of the three rotor blades about the axis of rotation is 1470kgm²
what is an Electrical transformer?
Answer:
A transformer is a passive electrical device that transfers electrical energy from one electrical circuit to another, or multiple circuits.
Explanation:
Hope it helps
Answer:
A transformer with eletric abilities.
Explanation:
Select the correct term to complete each sentence. If you the wavelength, the electromagnetic radiation energy will double. The energy of the electromagnetic radiation will if you halve the wavenumber. When the frequency of the light is doubled, its energy will
Answer:
A) If you halve the wavelength, the electromagnetic radiation energy will double.
B) The energy of the electromagnetic radiation will halve if you halve the wavenumber.
C) When the frequency of the light is doubled, its energy will double.
Explanation:
The function for the light frequency is given as
The energy supplied to each electron is doubled by halving the wavelength, nearly doubling its kinetic energy by two after it is free from the metal. It is important to remember that for a given period of time, the number of electrons ejected will remain constant.
Cheers
Electromagnetic waves is what type of energy
Answer:
Energy waves that have both an electric and magnetic field.
Explanation:
A penny and a quarter are embedded in the concrete bottom of a swimming pool filled with water. Which of these coins experiences the greater downward force due to water pressure acting on it? Explain.
Answer: The quarter, because it has a larger surface area.
Explanation:
remember the equation:
Pressure = Force/Area
Now, if we isolate Force, we get:
Force = Pressure*Area.
The pressure will be the same for both coins, but the area is not.
Then the one with a larger surface area will suffer a greater downward force. (We can consider the area as the area of the top or bottom of the coin)
The area of a circle of diameter d, is:
A = pi*(d/2)^2
where pi = 3.14
The penny has a diameter of 19.05 mm, then its area is:
A = 3.14*(19.05mm/2)^2 = 284.87mm^2
The quarter has a diameter of 24.26mm, then the area is:
A = 3.14*(24.26mm/2)^2 = 462 mm^2
Then the quarter has a larger area, this means that the quarter will experience the greater downward force due to water pressure.
A block of wood is floating in a pool of water. How does the volume of water displaced by the block compare to the volume of the block?
Answer:
The volume of water displaced the same as the volume of the block.
Explanation:
With respect to the principle of floatation, when an object floats in a fluid; its weight is the same as the volume of the fluid displaced.
The volume of the block relates to is dimension and size which can be compared with the volume of the fluid displaced. When the block is floats in water, it would displace a reasonable volume of water. Thus, it would be expected that the volume of water displaced by the block is equal to the volume of the block.
An object has a kinetic energy Ek. What happens to the kinetic energy if we:
(a) double m?
(b) triple v?
An object is floating in equilibrium on the surface of a liquid. The object is then removed and placed in another container, filled with a less dense liquid. What would you observe?
Answer:
The fraction of its volume inside liquid is increased .
Explanation:
According to principle pf floatation , an object floats on the surface of water
when the weight of liquid displaced by it becomes equal to weight of the object . weight of the liquid depends upon the density of the liquid .
In the second case , when the body is dipped into liquid of lesser density , in order to balance the weight of body , more volume of liquid will be displaced so that weight of displaced liquid becomes equal to object's weight . So the body floats with greater depth inside liquid . The fraction of its volume inside liquid is increased .
Which statement is supported by this scenario?
Yanni is sitting in the stands watching a football game.
The quarterback runs forward toward the end zone
and throws a pass straight downfield to a player for a
touchdown. The quarterback ran at a speed of 8 m/s
and threw the ball with a speed of 15 m/s.
For Yanni, the speed of the ball is 23 m/s, and for
the quarterback, the speed of the ball is 15 m/s.
For Yanni, the speed of the ball is 15 m/s, and for
the quarterback, the speed of the ball is 8 m/s.
For both Yanni and the quarterback, the speed of
the ball is 23 m/s.
For both Yanni and the quarterback, the speed of
the ball is 15 m/s.
Answer:
A
For Yanni, the speed of the ball is 23 m/s, and for the quarterback, the speed of the ball is 15 m/s.
Explanation:
Right on edge 2021
The statement supported by this scenario is, for Yanni, the speed of the ball is 23 m/s, and for the quarterback, the speed of the ball is 15 m/s.
Relative speed of the ballThe relative speed of the ball is determined with respect to frame of reference.
For Yanni at rest ( zero speed);Vr/b = va + vb
Vr/b = 8 + 15 = 23 m/s
For quarterback in motionVr/b = va + vb
Vr/b = 0 + 15 = 15 m/s
Thus, the statement supported by this scenario is, for Yanni, the speed of the ball is 23 m/s, and for the quarterback, the speed of the ball is 15 m/s.
Learn more about relative speed here: https://brainly.com/question/17228388
#SPJ2
An atomic nucleus is composed of
Answer:
84 protons and 128 neutron
If an 800.0 Kg sports car slows to 8.0 m/s in the forward direction to check out an accident scene and a 1200.0 kg pick-up truck behind them continues traveling at 15.0 m/s forward, with what velocity will the two move if they lock bumpers after a rear-end collision
Answer:
12.2m/sExplanation:
Step one:
given data
mass m1=800kg
velocity v1=8m/s
mass m2= 1200kg
velocity v2=15m/s
Note: the two bodies move with the same velocity after collision, hence the common velocity is v=?
Step two:
the expression for the total momentum is
m1v1+m2v2=v(m1+m2)
substituting we have
800*8+1200*15=v(800+1200)
6400+18000=v(2000)
24400=2000v
divide both sides by 2000 to find v
v=24400/2000
v=12.2m/s
Their common velocity is 12.2m/s
the wavelength produce by a shallow water body is 200mm. If the refractive index is 0.5. calculate the wavelength in deep water
Answer:
400mm
Explanation:
Refractive index is the ratio of the wavelength in the shallow water to that in deep water.
Refractive index = λs/λd
Given
Refractive index = 0.5
λs = 200mm
Required
0.5 = 200/λd
λd = 200/0.5
λd = 400mm
Hence the wavelength in deep water is 400mm
what is the acceleration of a 5kg object pushed by 50 n
Answer:
i think it is 10m/s^2
force divide by mass
What is the period of revolution about the Sun for an asteroid with a semimajor axis of 3 AU in the middle of the asteroid belt?
Answer:
The period of revolution is 5.2 years.
Explanation:
The period of revolution about the Sun for an asteroid can be found using Kepler's third law:
[tex] p^{2} = a^{3} [/tex] (1)
Where:
p: is the period =?
a: is the semimajor axis (average distance from Sun) = 3 AU
By entering "a" value into equation (1) we have:
[tex] p = \sqrt{a^{3}} = \sqrt{(3)^{3}} = 5.2 y [/tex]
Therefore, the period of revolution about the Sun for an asteroid in the middle of the asteroid belt is 5.2 years.
I hope it helps you!
A frog leaps with a displacement equal to vector u and then leaps with a displacement equal to vector v, as
shown below.
Answer:
The answer is B on khan academy
Explanation:
A frog leaps with a displacement equal to vector u and then leaps with a displacement equal to vector v, as shown below.
Which diagram(s) shows a valid way to find the frog's total displacement?
THE ANSWER IS IN THE ATTACHMENT!
Mechanical energy appears in the form of _____ energy and _____ energy.
Answer:
Potential and kinetic
Explanation:
If you are doing ck12 this is the answer
A train of mass 3.3 × 10^6 kg is moving at a constant speed up a slope inclined at an angle of 0.64°
to the horizontal. The engine of the train is producing a useful output power of 14 MW.
Assume that there are no frictional forces opposing the motion of the train.
What is the speed of the train?
A 0.43 m s–1 B 4.2 m s–1 C 39 m s–1 D 380 m s–1.
Ans is C how?
ref: Q14 - 9702_s18_qp_11
Answer:
C. 39 m/s
Explanation:
First we need to calculate the total force required to move the train along the inclined plane. So, it is clear that the work done will be equal to the component of the weight that is parallel to the inclined plane, because there is no frictional force present:
Force = F = mg Sin θ
where,
m = mass of train = 3.3 x 10⁶ kg
g = 9.8 m/s²
θ = Angle of Inclination = 0.64°
Therefore,
F = (3.3 x 10⁶ kg)(9.8 m/s²)Sin 0.64°
F = 3.612 x 10⁵ N
Now, the formula for power is:
P = FV
V = P/F
where,
V = Velocity of Train = ?
P = Power of Engine = 14 MW = 1.4 x 10⁷ W
Therefore,
V = 1.4 x 10⁷ W/3.612 x 10⁵ N
V = 38.75 m/s
which is approximately equal to:
C. 39 m/s
The speed of train is 39 m/s. Hence, option (C) is correct.
Given data:
The mass of train is, [tex]m = 3.3 \times 10^{6} \;\rm kg[/tex].
The angle of inclination is, [tex]\theta = 0.64^ {\circ}[/tex].
The useful power output value is, [tex]P= 14 \;\rm MW = 14 \times 10^{6} \;\rm W[/tex].
The work done will be equal to the component of the weight that is parallel to the inclined plane, because there is no frictional force present. So, the total force required to move the train along the inclined plane is given as,
[tex]F = mg sin \theta\\\\F = 3.3 \times 10^{6} \times 9.8 \times sin0.64\\\\F = 361233.75 \;\rm N[/tex]
Now, use the formula of the power to obtain the value of speed as,
[tex]P = F \times v\\\\14 \times 10^{6} =361233.75 \times v\\\\v \approx 38.75 \;\rm m/s[/tex]
Thus, the speed of train is 39 m/s. Hence, option (C) is correct.
Learn more about the power output here:
https://brainly.com/question/22285866
Which best describes the law of conservation of mass? The coefficients in front of the chemicals in the reactants should be based on the physical state of the products. Products in the form of gases are not considered a part of the total mass change from reactants to products. When reactants contain both a solid and a liquid, the solid counts toward the overall mass and the liquid does not. O The mass of the reactants and products is equal and is not dependent on the physical state of the substances.
Answer:
Explanation:
1. when both sides of the reactants and the products are equal
like h+oh ⇒ h20
hydrogen has 2 atoms on both sides and oxygen has one on both sides
2. no they are put to balance the equation
3. nope they are treated equally as all the other states
4. no if u are talking about a formula unit like NaCl for example it is aqueous not each element taken on its own if u are talking about just elements then i said before all states are treated equally
5. yup
The shortest wavelength of visible light is approximately 400 nm express the wavelength in centimeters
Answer:
4x [tex]10^{-5}[/tex] cm
Explanation:
400nm = 400 x [tex]10^{-9}[/tex] m
1m = 100 cm
400 x [tex]10^{-9}[/tex] m = 400 x [tex]10^{-9}[/tex] x 100 cm
ans : wavelength of light = 4x [tex]10^{-5}[/tex] cm
Answer:
[tex]4 * 10^{5}[/tex]
Explanation:
[tex]1c m = 1*10^-{7}nm[/tex]
A 180-kg load is hung on a wire of length of 4.70 m, cross-sectional area 2.000 10-5 m2, and Young's modulus 8.00 1010 N/m2. What is its increase in length?
i saw it online once but i cant find it so i would look this up on maybe quizlet i use it a lot and it helps
What is energy?
Question 1 options:
force × distance
force
chemical change
the ability to do work
Answer:
The ability to do work
Explanation:
Energy can be defined as the ability to do work. We apply energy in basically everything we do in life, energy is needed to walk or move from one position to another, it is required to eat and do other basic things of life. The body system converts the food that is being consumed into energy, this energy can be switched from one form to another.
There are various forms of energy which include solar energy , wind energy, electrical energy, mechanical energy, kinetic energy, potential energy etc. This forms of energy can be converted from one form to anothe but cannot be destroyed.
Answer:
ability to work
Explanation:
HELPPP MEEE PLEADEEEE How could a cow have more momentum than a tiger ? Explain
Answer:
If a cow has a greater mass than the tiger, it has greater momentum, but only if they are moving at the same speed, or the tiger is going slower (i think)
Explanation:
the quantity of motion of a moving body, measured as a product of its mass and velocity.
What is the horizontal component of a ball thrown at a 27 degree angle at 16 m/s?
Answer:
14.25 m/s
Explanation:
In this problem, we need to find the horizontal component of a ball thrown at a 27 degree angle at 16 m/s.
It can be given by :
[tex]v_x=v\cos\theta\\\\=16\times \cos(27)\\\\=14.25\ m/s[/tex]
So, the horizontal component of the ball is 14.25 m/s.
A double slit is illuminated simultaneously with orange light of wavelength 600 nm and light of an unknown wavelength. The m=4 bright fringe of the unknown wavelength overlaps with the m=3 fringe of the orange light. What is the unknown w
Answer:
Explanation:
distance of 4 th bright fringe of unknown light = distance of 3 rd bright fringe of orange light . Let λ be wavelength of unknown light .
4 λ D / d = 3 x 600 x D / d
4 λ = 3 x 600
λ = 450 nm .
How fast does water flow from a hole at the bottom of a very wide, 7.1 mm deep storage tank filled with water
Answer:
The water will move fasterExplanation:
This happens as part of the consequences of the continuity of an incompressible fluid, of which water is an example.
so as the water emerges from the wider section the flow velocity increases and vice versa.
Hence the flow velocity in indirectly proportional to the area
The continuity equation is given below for our analysis
[tex]A1V1=A2V2\\[/tex]-------------------1
where
A1= the area of the wider section of the tank
V1= the flow velocity from the wider section
A2= the area of the hole at the bottom
V2= velocity of flow at the bottom.