Friday

December 9, 2016
Number of results: 38,871

**Chemistry**

Neutron diffraction is used in determining the structures of molecules. (a) Calculate the de Broglie wavelength of a neutron moving at 9.00% of the speed of light. __ m (b) Calculate the velocity of a neutron with a wavelength of 65 pm (1 pm = 10-12 m). __m/s

*October 21, 2008 by Rita*

**chemistry ap!!!**

Neutron diffraction is an important technique for determining the structures of molecules. Calculate the velocity of a neutron needed to achieve a wavelength of 0.989 Å. i used the equation and got 4.37, but its not right! pleas help someone

*October 19, 2011 by kela*

**Chemistry**

Neutron stars are composed of solid nuclear matter, primarily neutrons. Assume the radius of a neutron is approx. 1.0 x 10^-13 cm. Calculate the density of a neutron. [Hint: For a sphere V=(4/3) pi r^3. Assuming that a neutron star has the same density as a neutron, calculate ...

*October 11, 2015 by Anonymous*

**chemistry**

assuming that a neutron star has the same density as a neutron, calculate the mass in kilograms of a small piece of a neutron star the size of a spherical pebble with a radius of 0.11mm

*May 4, 2012 by Karon*

**chemistry**

Assuming that a neutron star has the same density as a neutron, calculate the mass in kilograms of a small piece of a neutron star the size of a spherical pebble with a radius of 0.30mm .

*February 9, 2014 by Anonymous*

**Chemistry**

A beam of neutrons (mneutron = 1.6749 x 10^-24 g) has a velocity of 1.44 km/hour. What is the wavelength of the neutron wave? The answer is 993 nm. I tried to use 1/2mv^2=hc/lambda but I got 1483.5 m

*December 8, 2008 by Shaniquaa*

**chemistry**

if the radius of a neutron is 1.0 x 10 minus 13cm calculate the density of a neutron in g/cm 3

*May 4, 2012 by Karon*

**Physics**

The interatomic spacing in a crystal of table salt is 0.281 nm. This crystal is being studied in a neutron diffraction experiment, similar to the one that produced the photograph in the figure. How fast must a neutron (mass = 1.67 x 10^-27 kg) be moving to have a de Broglie ...

*April 22, 2012 by Matt*

**Physics**

"A wave travels from one medium to another, and the wavelength decreases. What happens to the velocity and the frequency?" I know that frequency will remain the same, because it is controlled only by the source. But does the velocity decrease? According to Snell's law, ...

*July 22, 2010 by Stuck*

**physics**

Calculate the frequency in hertz, wavelength in nm, and the velocity in m/s of light inside a material with a refractive index of 1.39. In vacuum, the light has a wavelength of 514.5nm

*April 5, 2011 by noel*

**physics**

5)a. Electrons accelerated by a potential difference of 12.23 V pass through a gas of hydrogen atoms at room temperature. Calculate the wavelength of light emitted with the longest possible wavelength. b. Calculate the wavelength of light emitted with the shortest possible ...

*April 13, 2008 by Sandhya*

**Physics (Simple Frequency Question) Reply SOON!**

I know that... wavelength = velocity * frequency frequency = velocity/wavelength If I have the voltage and the wavelength, does the voltage count as the velocity to find the frequency? If not, how do I find the frequency when I know the intensity, wavelength, and voltage? Thanks!

*May 8, 2009 by Judy*

**Physics**

Ok, I have few questions which I solved but the answers in he book do not match with the ones that I got. Q1. The de-Brogile wavelength of a neutron at 927 degree C is {lambda}. What will be its wavelength at 27 degree C? I got 2 {lambda}, book says {lambda}/2 Q2. The distance...

*October 20, 2016 by new user*

**Chemistry**

At what speed must a neutron travel to have a wavelength of 9.2 pm?

*June 12, 2011 by Lance*

**physics **

what is the wavelength of neutron (m=1.67x10^-27kg) travelling at 3.0x10^4 m/s?

*June 16, 2013 by ceci*

**physics**

The volume of a neutron is about 10−45 cubic meters. Suppose you packed the number of neutrons you found for problem 4 into a cube so that the neutrons touched edge to edge. How big would the cube be? (Hint: Problem 4 states that a neutron star has a mass of 3.4×1030 kg...

*November 27, 2011 by Anonymous*

**Physics**

A neutron collides elastically with a helium nucleus (at rest initially) whose mass is four times that of the neutron. The helium nucleus is observed to rebound at an angle θ'2 = 44° from the neutron's initial direction. The neutron's initial speed is 7.0 105 m/s. ...

*March 7, 2010 by Ben*

**Physics**

A neutron collides elastically with a helium nucleus (at rest initially) whose mass is four times that of the neutron. The helium nucleus is observed to rebound at an angle θ'2 = 44° from the neutron's initial direction. The neutron's initial speed is 7.0 105 m/s. ...

*March 7, 2010 by Ben*

**chemistry**

A particle wavelength (λp) of a proton is 10-12m. What is the velocity of this proton [m/s]? To achieved the velocity that you just computed, what must have been the potential difference (V) through which the proton was accelerated? An electron of wavelength 1.74*10-10m ...

*March 23, 2013 by schoolgirl*

**General Physics**

A neutron collides elastically with a helium nucleus (at rest initially) whose mass is four times that of the neutron. The helium nucleus is observed to rebound at an angle è'2 = 45° from the neutron's initial direction. The neutron's initial speed is 6.6x10^5 m/s. Determine...

*October 30, 2008 by Scott*

**chemistry**

Atoms of ionized lithium gas (Li2+) are struck by neutrons moving at a velocity of 1.46e5 m/s. Calculate the shortest wavelength in the emission spectrum of Li2+ under these circumstances. You can assume that all electrons start in the ground state. Enter the wavelength in m:

*March 23, 2013 by schoolgirl*

**physics**

A neutron collides elastically with a helium nucleus (at rest initially) whose mass is four times that of the neutron. The helium nucleus is observed to move off at an angle =45. The neutron's initial speed is 3.8×105 .

*March 29, 2010 by Anonymous*

**PHYSICS**

A nuclear reactor contains nuclei that fission when bombarded by slow neutrons. The fission reaction produces fast neutrons which need to be moderated (i.e. slowed down) in collisions before they can cause further fissions. In this problem we consider a reactor which uses ...

*March 28, 2011 by Megan*

**CHEMISTRY**

What would be the uncertainty in velocity (miles/hr) of a neutron beam particle if the position can be measured within +/- 25 angstroms. The rest mass of a neutron = 1.67493 X 10^-27 kg or 1.008664904(14) amu. I know you have to use the heisenberg uncertainty principle: (...

*November 7, 2007 by Jacob*

**Physics**

I am having some trouble with some questions and need some help. A neutron with a mass of 1.68 x10(-27) exponent kg moves from a nuclear reactor with a velocity of 3.22 x10 (3) exponent m/s. What is the Broglie wavelength? Also, I need to write tge complete electron ...

*December 4, 2009 by Doly V*

**physics**

Assume that the mass of a neutron star is 1.5 times that of the Sun and the radius of the neutron star is 10 km. Ignore effects of Special Relativity. What is the approximate speed at which an object released from far away (at zero speed) reaches the surface of a neutron star...

*December 25, 2013 by Al*

**Physics**

A neutron collides elastically with a helium nucleus (at rest initially) whose mass is four times that of the neutron. The helium nucleus is observed to move off at an angle of 45 degrees. The neutron's initial speed is 5.9×105 m/s. Determine the speeds of the two particles ...

*October 8, 2010 by Bartholomew*

**college physics**

In a nuclear reactor, neutrons released by nuclear fission must be slowed down before they can trigger additional reactions in other nuclei. To see what sort of material is most effective in slowing (or moderating) a neutron, calculate the ratio of a neutron's final kinetic ...

*March 18, 2010 by Kyle*

**Physics**

A string is 2.4 m long, and the speed of sound along this string is 450 m/s. Calculate the frequency of the wave that would produce a first harmonic. Assume the string has nodes at both ends. What I've Tried Ln=2.4m v= 450 m/s f=? n=2 Ln=(4-1)/4 * Wavelength Wavelength = 2.4m/...

*April 17, 2016 by AlphaPlus*

**physics**

A tuning fork produces a wave at 280 Hz and with a wavelength of 1.5 m. Calculate its velocity.

*July 8, 2011 by wendell*

**science**

Calculate the de Broglie wavelength of a 0.44 kg ball moving with a constant velocity of 26 m/s (about 60 mi/h).

*April 2, 2013 by annie*

**Chemistry**

Calculate the de Broglie wavelength associated with a body of mass 1.5 kg moving with a velocity of 100m/s.

*October 21, 2012 by Sparkle*

**science **

if the velocity of a progressive wave with a periodic frequency of 10KHz is 330m/s. calculate it's wavelength.

*July 10, 2016 by iornav Gideon *

**science **

if the velocity of a progressive wave with a periodic frequency of 10khz is 330m/s.calculate it's wavelength.

*July 14, 2016 by versatile *

**Physics**

This is a very confusing question and I have no idea how to tackle it. - In a nuclear reactor, neutrons released by nuclear fission must be slowed down before they can trigger additional reactions in other nuclei. To see what sort of material is most effective in slowing (or ...

*October 30, 2009 by Sal*

**physics**

A neutron in a reactor makes an elastic head-on collision with a nitrogen atom that is initially at rest. (The mass of the nitrogen nucleus is about 14 times that of the neutron.) (a) What fraction of the neutron's kinetic energy is transferred to the nitrogen nucleus? (b) If ...

*October 28, 2012 by heather*

**Chemistry**

What is the de Broglie wavelength of an oxygen molecule, O2 traveling at 521 m/s? Is the wavelength much smaller or much larger than the diameter of an atom. (on the order of 100 pm) De Broglie wavelength = h/mv h = Planck's constant in J*s. m is mass in kg. v is velocity in m...

*November 3, 2007 by Lauren*

**science**

Where does the neutron of heliam come from although hydrogen has no neutron?

*November 12, 2007 by Adina*

**physics**

A neutron, a proton, and an electron are initially at the same distance from a relatively large stationary nucleus moving at a constant velocity. Assume the masses of the proton and neutron are equal. 1. Which is the first particle to reach the nucleus? 2. Which particle ...

*March 23, 2008 by Karen*

**PHYSICS!!!**

A neutron, a proton, and an electron are initially at the same distance from a relatively large stationary nucleus moving at a constant velocity. Assume the masses of the proton and neutron are equal. 1. Which is the first particle to reach the nucleus? 2. Which particle ...

*March 23, 2008 by Karen*

**susane**

I have a question concerning waves. What effect does increasing the tension in a vibrating string have upon wavelength? I was thinking that as the weight increases more standing waves are created. As more standing waves are created, the wavelength decreases. I have one more ...

*February 3, 2007 by Physics*

**physic**

Neutron stars are extremely dense objects with a mass comparable to the mass of the sun but a radius of only several thousand meters. Consider a neutron star of mass M = 1.99e+030 kg and a radius of R = 10 km. g = 1.3279e12 m/s Assuming uniform density, how much would 1.1 ...

*May 23, 2007 by x*

**physics**

A neutron with a mass of 1.67x10^-27 kg traveling east with a kinetic energy of 2.00x10^-21J collides perfectly elastically with helium nucleus with a mass 6.68x10^-27 kg that is initially at rest. After the collision, the neutron has a kinetic energy 1.80x10^-21J. What angle ...

*November 9, 2014 by Johnny*

**Physics**

A neutron with a mass of 1.67x10^-27 kg traveling east with a kinetic energy of 2.00x10^-21J collides perfectly elastically with helium nucleus with a mass 6.68x10^-27 kg that is initially at rest. After the collision, the neutron has a kinetic energy 1.80x10^-21J. What angle ...

*November 12, 2014 by Johnny*

**Physics**

A neutron with a mass of 1.67x10^-27 kg traveling east with a kinetic energy of 2.00x10^-21J collides perfectly elastically with helium nucleus with a mass 6.68x10^-27 kg that is initially at rest. After the collision, the neutron has a kinetic energy 1.80x10^-21J. What angle ...

*November 12, 2014 by Johnny*

**Chemistry**

What is the wavelength in nanometers of a photon with a frequency of 6.10 ✕ 10^14 sec-1? (The speed of light in a vacuum is 2.998 ✕ 108 m/s. Planck's constant is 6.626 ✕ 10^-34 J·s.) I know that speed of light = wavelength * velocity, but I don't know ...

*September 23, 2015 by Petyon *

**College Physics II**

1) An electron moving with a speed of 2.84E+6 m/s has the same momentum as a photon. Calculate the de Broglie wavelength of the electron. 2) Calculate the wavelength of the photon.

*November 25, 2010 by VJC*

**Chemistry**

A 0.22-caliber handgun fires a 27-{\rm g} bullet at a velocity of 765 {\rm m}/{\rm s}. Part A Calculate the de Broglie wavelength of the bullet.

*June 30, 2012 by Anonymous*

**Chemistry**

The ionization energy of hydrogen is 1313 kJ/mol. Covert this energy to: wavelength (nm) 1/wavelength, reciprocal wavelength (cm^-1) spectral region? (IR, visible, UV, etc.) I know E=hv=hc/wavelength h=6.62 x 10^-34 J-s c= 3x10^8 v=c/wavelength But for some reason trying to ...

*December 7, 2012 by Sarah*

**Chemistry**

When the ratio of neutron-to-proton dictates that a neutron must break down it will form a helium nucleus an alpha particle a proton and an electron*** Two protons

*June 1, 2016 by James*

**physics**

a neutron of mass 1.67*1o power of (-27) is moving with a velocity 10 to the power of(6) collides with a deuteron of mass 3.34*10 to the power of (-27) kg at rest .after collision if both have single particle find its velocity

*April 11, 2012 by srikala*

**Chemistry**

Im not exactly sure what how to solve this with the way my teacher asked this question. "For hydrogen atom transitions calculate E, v, and wavelength:" Ni= 1 li= 0 Mli= 0 Msi= -1/2 Nf= 2 Lf= 0 Mlf= 0 Msf= -1/2 E(kj)= ? v(Hz)= ? wavelength(m)= ?

*May 3, 2014 by Mary*

**Chemistry **

A 0.22-caliber handgun fires a 27-g bullet at a velocity of 765 m/s. Calculate the de Broglie wavelength of the bullet. Is the wave nature of matter significant for bullets?

*March 28, 2012 by danielle*

**Standing waves and resonance (physics)**

A nylon string has a linear density of 7.2g/m and is under a tension of 150N. The fixed supports are 90cm apart. The string is oscillating in the standing wave pattern. Find a)speed b)wavelength c) frequency v=sqr(F/u(linear density) v=sqrt(150N/7.2g/m) = 4.56m/s b) wavelength...

*February 6, 2007 by Susane*

**Chemistry (Electrons in Atoms)**

The wavelength of visible light varies from 0.40 μm to 0.70 μm as the color of the light changes from violet to red. Calculate the energy of a photon whose wavelength is 0.67 μm HINT: From the wavelength and the speed of light, we can get the frequency. Then the...

*May 23, 2011 by Katie*

**chemistry 1**

How do you write balanced equations A. Neutron emission by 88Br B. Electron absorption by 116Sb C. Positron emission by 184Hg D. Alpha emission by 229Th E. Neutron capture by 200Hg

*October 25, 2013 by Alexus*

**PHYSICAL SCIECE**

A seismic wave has a velocity of 5000 m/s and a frequency of 4Hz. wht is the wavelength of this wave? if this was a light wave traveling in a vacuum with the same wavelength, what would be its period?

*July 14, 2011 by CARLOS*

**chem**

the wavelength of ligh is 310 nm. calculate the frequency? what is the wavelength of electromagnetic radiation if its frequency is 3.2 X 10 -2(exponent) Hz??

*November 8, 2007 by Amanda*

**science waves**

how do you calculate the frequency when...when you do not know the wavelength...and same about finding wavelength when frequency is given????

*May 18, 2008 by ashley*

**Physics**

I need help solving this please! I think that for part (b) I can use energy and wavelength to solve for frequency and the one with the highest frequency is the most damaging, but I'm not sure what to do for part (a). You want to study a biological specimen by means of a ...

*August 15, 2010 by Brianna*

**chem plz help!**

the rate of a nuclear reaction can be changed by?? i know adding a catalyst to a normal reaction can but to a nuclear im not sure. increasing temp decreasing pressure adding a catalyst none I suppose it all depends upon how you define a catalyst. Perhaps in a small way ...

*April 30, 2007 by luis*

**Chemistry**

1.a radioscope which is neutron poor and very heavy is most likely to decay by? alpha , beta, electron capture, positron emission 2. When a 235-U nucleus is struck by a thermal neutron, fission occurs often with the release of neutrons. If fission fragments are 89-Sr and 144-...

*April 27, 2007 by keith*

**CHEM**

I just have a couple of questions that I need some help with: 1) A 0.22-caliber handgun fires a 27g bullet at a velocity of 765m/s. Calculate the de Broglie wavelength of the bullet. Express your answer using two significant figures in meters. ~and~ 2) An X-ray photon of ...

*November 5, 2007 by K*

**chemistry**

The De Broglie wavelength of electrons used in an experiment utilizing an electron microscope is 96.00pm. what is the speed of one of these electrons? (De Broglie's equation is wavelength=6.63E-34 / (mass*velocity))

*November 11, 2015 by Brooke N*

**Chemistry**

Calculate the wavelength of light emitted when each of the following transitions occur in the hydrogen atom. (a) n = 5 n = 4 _________nm (b) n = 5 n = 3 _____________ nm (c) n = 5 n = 2 __________ nm Calculate the maximum wavelength of light capable of removing an electron for...

*October 20, 2008 by Giznelbell*

***physics***

Electrons accelerated by a potential difference of 12.87 V pass through a gas of hydrogen atoms at room temperature. Calculate the wavelength of light emitted with the longest possible wavelength. I don't know what equation to use. Any help would be greatly appreciated.

*March 24, 2008 by Beth Macbeth*

**Chemistry**

Can u show me how to calculate the neutron-to-proton ratio of an atom? For example: tin-134 or silver-107

*April 12, 2010 by Tammy*

**Wavelength PLEASE HELP**

Calculate the wavelength of the signal sent by Q101 assuming that the actual frequency is 101.1 MHz. Determine how long it would take the signal to reach a car 33.4km away from the station. THANK YOU!

*May 22, 2013 by Mike Jones*

**science**

In a water tank,on throwing a stone 20 full ripples are produced in 1 sec.the distance a crest and a through is 10 cm.calculate: (a) the wavelength of ripple (b) frequncy of ripple (c) velocity of the ripples.

*February 3, 2015 by saurav*

**Physics**

10. A military jet flies horizontally with a velocity of 450 m/s and 20,000 m above the ground. When the jet is straight above an artillery gun a shell is fired. Assuming the shell hits the jet. a. Calculate the horizontal component of the initial velocity of the shell. b. ...

*September 20, 2015 by Zachary Star*

**physics**

Find the threshold energy that the incident neutron must have to produce the reaction 1 n 0 + 4 He 2---> 2 H 1 + 3 H 1 For this, like the 1 n 0<--- it is supposed to be written like 1 on the top 0 on the bottom next to n. like the atomic number of neutron and the other ...

*February 16, 2007 by jaimie*

**Neutron star-universal gravitational problem**

Hi, i'm having problem w/ this question...i've tried everything i know and i still don't get the right answer...here's the info they give: Consider a neutron star of mass M = 1.99e+30kg and a radius of R = 10 km. They ask 3 question...two of which i have answered (1st:...

*August 4, 2005 by Marcus Jasp*

**physic**

Assuming uniform density, how much would 1.1 cubic centimeters of neutron star material weigh on the surface of the earth? You need the density of the neutron star to do this. weight= mass*g=density*volume*g

*May 23, 2007 by x*

**physics(waves)**

A wave has a speed of 340m/s and a period of 0.28ms. what's the wavelength? so I worked this and I got 95.2m but the answer to d question says 0.095m. period(T) = 1/F (since F = 1/T) therefore, F = 1/0.28 = 3.5714 wavelength = velocity/frequency w = 340/3.5714 = 95.2m (Isn't ...

*February 23, 2015 by Francis *

**AP Chemistry**

A mixture of argon and mercury vapor used in advertising signs emits light of wavelength 610 nm. Calculate the energy change resulting from the emission of 1.00 mol of photons at this wavelength. Answer in units of kJ/mol.

*November 30, 2010 by Billy*

**Physics**

Neutron stars consist only of neutrons and have unbelievably high densities. A typical mass and radius for a neutron star might be 5.8 x 1028 kg and 1.5 x 103 m. (a) Find the density of such a star. (b) If a dime (V = 2.0 x 10-7 m3) were made from this material, how much would...

*November 23, 2012 by StressedStudent*

**physics 1**

Neutron stars consist only of neutrons and have unbelievably high densities. A typical mass and radius for a neutron star might be 5.6 x 1028 kg and 1.5 x 103 m. (a) Find the density of such a star. (b) If a dime (V = 2.0 x 10-7 m3) were made from this material, how much would...

*April 22, 2014 by Anonymous*

**physics 1**

Neutron stars consist only of neutrons and have unbelievably high densities. A typical mass and radius for a neutron star might be 5.6 x 1028 kg and 1.5 x 103 m. (a) Find the density of such a star. (b) If a dime (V = 2.0 x 10-7 m3) were made from this material, how much would...

*April 22, 2014 by Anonymous*

**physics**

Green light has a wavelength of 4.96 10-7 m and travels through the air at a speed of 3.00 108 m/s. Calculate the period of green light waves with this wavelength. s What is the frequency? Hz

*March 12, 2011 by Jesse*

**physics**

Green light has a wavelength of 4.96 10-7 m and travels through the air at a speed of 3.00 108 m/s. Calculate the period of green light waves with this wavelength. s What is the frequency? Hz

*March 13, 2011 by Anonymous*

**chemistry**

Calculate the energy of a photon of wavelength 3.1 µm with that of wavelength 0.166 nm. What I Got: 3.1 µm photon: 6.36x10^22j 0.166nm photon: 1.23x10^19j Also, what region of the electromagentic spectrum would each of these measurements belong to?

*February 8, 2015 by alex*

**general physics**

Neutron stars consist only of neutrons and have unbelievably high densities. A typical mass and radius for a neutron star might be 6.3 x 1028 kg and 1.6 x 103 m. (a) Find the density of such a star. (b) If a dime (V = 2.0 x 10-7 m3) were made from this material, how much would...

*July 20, 2013 by please help with these practice problems*

**Chemistry**

Atoms of ionized lithium gas (Li2+) are struck by neutrons moving at a velocity of 1.46e5 m/s. Calculate the shortest wavelength in the emission spectrum of Li2+ under these circumstances. You can assume that all electrons start in the ground state.

*March 22, 2013 by Sam Chem*

**science**

What is the wavelength of waves transmitted by an AM radio station operating at a frequency of 840 kilohertz? Calculate the energy of a photon whose frequency is 2450 megahertz What is the difference in energy for a photon of ultra-violet radiation, wavelength 319 nm and a ...

*December 5, 2012 by anna*

**physics**

For a particular type of wave in a particular medium why must f and lambda be inversely proportional. Frequency deals with the number of waves per second, while wavelength deals with the distance from peak to peak. It would be inversely proportional because lambda deals with ...

*February 18, 2007 by susan*

**Chemistry**

Heisenberg's uncertainty principle can be expressed mathematically as Δx*Δp = h/4π, where Δx and Δp denote the uncertainty in position and momentum respectively and h is Planck's constant. What would be the uncertaintry in the position of a neutron (...

*November 10, 2013 by Andy*

**Chemistry**

What would be the speed of the following particles if they had the same wavelength as a photon of green light (λ = 500.0 nm)? Proton (mass = 1.673*10^(-24)g) =_____ neutron (mass = 1.675*10(-24)g) =_____ electron (mass = 9.109*10^(-28)g) =_____ alpha particle (mass = 6....

*April 2, 2013 by Anonymous*

**Chemistry**

What would be the speed of the following particles if they had the same wavelength as a photon of green light (λ = 500.0 nm)? Proton (mass = 1.673*10^(-24)g) =_____ neutron (mass = 1.675*10(-24)g) =_____ electron (mass = 9.109*10^(-28)g) =_____ alpha particle (mass = 6....

*October 10, 2013 by Natalie*

**physics**

Calculate the magnitude of the electrostatic force the two down quarks inside a neutron exert on each other if they are separated by a distance of 0.71 fm.

*October 27, 2012 by melike*

**Physics HELP!!**

1. What is the longest wavelength for standing sound waves in a 133.9cm long tube that is open at both ends? b).What is the second longest wavelength? c).What is the third longest wavelength? d).What is the longest wavelength for a standing wave, in the same length tube, that ...

*November 30, 2012 by joane *

**Physics**

If a wavelength is doubled and velocity remains the same, is the frequency halved? I say "yes". If the velocity is halved and the wavelength remains the same, is the frequency halved. I say "yes" also. Am I correct?

*May 18, 2009 by NH*

**Physics**

A motorboat is traveling 5m/s East, and encounters a current traveling 2.5m/s, North. If the witdth of the river is 80m wide, how much time does it take the boat to reach the other shore. I understand how to calculate the resulatant velocity, but I don't understand why you use...

*October 20, 2010 by Jennifer *

**Chemistry**

1) Calculate the energy. in joules, of a photon of wavelength 1.250x 10^3 nm 2) If 3.011x 10^23 molecules have a mass of 20.04 grams, what is the molar mass of the substance? Is it 40.07g/mol? 3) 47.5g of Boron contains __________ atoms of B? Is it 2.65x10^24 4) What is the ...

*February 15, 2014 by Annabelle*

**Physics**

Rank in order the following according to their speeds, from fastest (1) to slowest (5): (i) 425-nm-wavelength light through a pane of glass, (ii) 500-nm-wavelength light through air, (iii) 540-nm-wavelength light through water, (iv) 670-nm-wavelength light through a diamond, ...

*February 2, 2013 by Cassie*

**chem**

What is the wavelength (in nm) of the line in the spectrum of the hydrogen atom that arises from the transition of the electron from the orbital with n =5 to the orbital with n = 2? Note, the line corresponds to the energy of the photon that is emitted in the transition. 4.34 ...

*October 26, 2012 by Anonymous*

**Physics**

NEED HELP On a flat battle ground, a catapult is used to launch a rock with a velocity of 25m/s at angle 30 degrees above the horizontal.? Sketch the situation and decompose the initial velocity vector. WHat are the initial values for Vx and Vy? Calculate the maximum height ...

*August 19, 2014 by Jeesha*

**Physics**

The following figure represents the ride for a cart with a mass of 200 kg along a frictionless track. a. Calculate the velocity of the cart at points A, B, and C if the cart is dropped from a height of 100m with a initial velocity of 10 m/s. b. Calculate the height of the ...

*July 25, 2014 by Liz*

**college Chemistry**

It requires 945.0 kJ/mol to break N2 molecules into atoms. Calculate the maximum wavelength of light that will still break these molecules apart. I tried converting the energy to kj and using E=hc/wavelength but that didn't give me the right answer...

*November 4, 2010 by alexis*

**college Chemistry**

It requires 945.0 kJ/mol to break N2 molecules into atoms. Calculate the maximum wavelength of light that will still break these molecules apart. I tried converting the energy to kj and using E=hc/wavelength but that didn't give me the right answer...

*November 4, 2010 by alexis*

**Chemistry**

An electron ps from the 6th to te 3rd energy level in the hydrogen atom: a) calculate the wavelength b) calculate the frequency c) calculate te enrgy d) into which spectral series would the photon be grouped? (i really just need to formulas, then i could solve myself...)

*May 23, 2011 by Ella*