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Blumblebee
01-18-2010, 04:58 AM
Ok, this are pretty simple but i havent really been paying attention so I don't get them one bit haha help would be appreciated.


A wave travels along a light spring. The length of this wave is 5.0x10^-1, and the frequency is 3.0 Hz. What is the length of the wave in the heavy spring if the speed in the heavy spring is 1.0 m/s?

thanks a bunch in advance (i might add more later)

Nava2
01-18-2010, 05:02 AM
If the frequency is constant, then would it not be 1/3?

Blumblebee
01-18-2010, 05:06 AM
If the frequency is constant, then would it not be 1/3?

how did you come to that? Haha i don't understand any of this shit.

Buckleyindahouse
01-18-2010, 07:40 AM
Wavelength formula




C=λv or λ=C/v
Frequency = Velocity divided by wavelength
C is the velocity, which is the speed of light ~3.00 × 108 m/sec
λ is the wavelength
v is the frequency


Thats the formula, it's simply multiplication. I'm also doing this in school.

Blumblebee
01-18-2010, 04:32 PM
Thats the formula, it's simply multiplication. I'm also doing this in school.

I understand the formula' ssomewhat, but when the wave is traveling to a faster medium, then certainly the frequency changes and so does the wavelength no? That's the part I do not understand, but maybe I'm just retarded.

silentwolf
01-18-2010, 07:09 PM
Thats the formula, it's simply multiplication. I'm also doing this in school.

I think you'll find this wave isn't travelling at the speed of light :p

I'd argue that you haven't been given sufficient information to answer the question. But the answer they probably want is:
v=fλ
λ=v/f
λ=1/3

I.e. frequency of the wave in both is the same.

Blumblebee
01-18-2010, 10:19 PM
silent wolf you are correct :) thank you everyone. I have 150 multiple choice due on wednesday so I'll have alot more questions coming

Blumblebee
01-19-2010, 04:22 AM
new questions:


A horizontal force of 15N is applied to a 4.0kg block sitting on a level surface for which the coefficient of friction is 0.30. What is the acceleration of the block?

a. it remains stationary.
b. 0.75 m/s^2
c. 0.81 m/s^2
d. the block does not accelerate




a baseball bat exerts a force of +950N on a 150g ball with an 800g bat. At the moment of impact, what is the respective acceleration of the ball and bat ?

a. Ball = -1.19x10^3 ; Bat = +6.33x10^3
b. Ball = -6.33x10^3; bat = +1.19x10^3
c. Ball = +6.33x10^3; bat = -1.19x10^3
d. Ball = +1.19x10^3; bat = -6.33x10^3


if you could provide explanation as i need to provide proof that i know how to solve the answer. Thanks :)

Main
01-19-2010, 08:04 AM
Thats the formula, it's simply multiplication. I'm also doing this in school.

This is Newtonian physics, don't get mistaken for quantum:) That equation is for sub atomic particles.

silentwolf
01-19-2010, 11:17 AM
new questions:


A horizontal force of 15N is applied to a 4.0kg block sitting on a level surface for which the coefficient of friction is 0.30. What is the acceleration of the block?

a. it remains stationary.
b. 0.75 m/s^2
c. 0.81 m/s^2
d. the block does not accelerate


a baseball bat exerts a force of +950N on a 150g ball with an 800g bat. At the moment of impact, what is the respective acceleration of the ball and bat ?

a. Ball = -1.19x10^3 ; Bat = +6.33x10^3
b. Ball = -6.33x10^3; bat = +1.19x10^3
c. Ball = +6.33x10^3; bat = -1.19x10^3
d. Ball = +1.19x10^3; bat = -6.33x10^3


if you could provide explanation as i need to provide proof that i know how to solve the answer. Thanks :)

Q1: F=ma, F=coeff_of_frection*reaction_force

reaction_force = mg

Plug the numbers in.


Q2: F=ma, a=F/m. c :)

Blumblebee
01-19-2010, 03:54 PM
This is Newtonian physics, don't get mistaken for quantum:) That equation is for sub atomic particles.

no he was correct, my first question differs from the area of my second.


Q1: F=ma, F=coeff_of_frection*reaction_force

reaction_force = mg

Plug the numbers in.


Q2: F=ma, a=F/m. c :)

hmm, I feel like a ritard. Thanks :)

marpis
01-24-2010, 10:08 PM
This is Newtonian physics, don't get mistaken for quantum:) That equation is for sub atomic particles.

v = labda * f
applies to all waves...