# Physics 11

Waves travelling along a string have a wavelength of 2.4m. When the waves reach the fixed end of the string, they are reflected to produce a standing wave pattern. How far from the end are the first 2 antinodes?

I know that each wavelength has 2 antinodes so each antinode has a length of 1.2m. I feel like I need either the amount of antinodes total or the total length of the string to get that value...

Thanks a bunch :)

1. 👍
2. 👎
3. 👁
1. the first antinode is 1/4 wavelength from the fixed end.
the second one is half a wavelength further
so at L/4 and 3L/4
= .6 and 1.8

the fixed end is a node x = 0
the ANTInode is 1/4 L away, x = L/4
the next node is at L/2 , x = L/2
next ANTInode is at 3L/4 x=(3/4)L
the next node is at x = L
DRAW IT

math
y = sin2pi (x/L - t/T) + sin2pi(x/L+t/T)

that is a wave going right plus a wave going left and not that at x = 0 the sum is always zero, that is a NODE
now do the trig
sina+sin b = 2sin.5(a+b)cos.5(a-b)
so here
y= 2 sin 2pi x/L cos 2pi t/T
now look at 2sin 2pi x/L
when x = 0 we have 2*0 = 0
when x = L/4 we have 2sinpi/2 = 2
our first antinode
when x = L/2 we have 2 sinpi = 0
wen x = 3L/4 we have 2 sin3pi/2 =-2
our second antinode
when x = L we have 2 sin 2pi = 0

1. 👍
2. 👎
2. Oh I get it!! Thank you very much :)

1. 👍
2. 👎
3. LOL i read this maybe... 6 times, then like you say - I DREW IT - and then it made sense < 3

1. 👍
2. 👎

## Similar Questions

1. ### Science

What is the main difference between mechanical and electromagnetic waves? A. Mechanical weaves involved transfers energy; electromagnetic waves do not B. Mechanical waves require a medium to travel in; electromagnetic waves do

2. ### Science

1. Which of the following statements about mechanical waves is true? a. mechanical waves require a medium to travel through b. mechanical waves do not have amplitude and wavelength c. mechanical waves do not have frequency d.

3. ### Physics

Earthquakes produce two kinds of seismic waves: he longitudinal primary waves (called P waves) and the transverse secondary waves (called S waves). Both S waves and P waves travel through Earth’s crust and mantle, but at

4. ### Science

What is the main difference between mechanical and electromagnet waves? a)Mechanical waves involve transfer of energy; electromagnet waves do not. b)Mechanical waves require a medium to travel in; electromagnet waves do not.

1. ### Physics

Two mirrors of a laser separated by 8.0 cm form an optical cavity in which standing waves of laser light can be set up. Each standing wave has an integral number n of half wavelengths in the 8.0 cm length, where n is large and the

2. ### Physics

A wave travels at a speed of 34 cm/s. It’s wavelength is 18 cm. What is the period of the wave? 0.75 s 1.2 s 0.66 s 0.53 s Regions of compression and rarefaction help define _______. Electromagnetic waves Longitudinal waves, but

3. ### Physics

A stretched string fixed at both ends is 2.0 m long. What are the three wavelengths that will produce standing waves on this string? Name at least one wavelength that would not produce a standing wave pattern, and explain your

4. ### Science

1. Which of the following statements about mechanical waves is true? Mechanical waves require a medium to travel through. Mechanical waves do not have amplitude and wavelength.** Mechanical waves do not have frequency. Mechanical

1. ### physics

An earthquake generates three kinds of waves: surface waves (L waves), which are the slowest and weakest; shear (S) waves, which are transverse waves and carry most of the energy; and pressure (P) waves, which are longitudinal

2. ### physics

In a double-slit experiment, two beams of coherent light traveling different paths arrive on a screen some distance away. What is the path difference between the two waves corresponding to the third bright band out from the

3. ### Algebra 1 high school

In deep water, the speed s (in meters per second) of a series of waves and the wavelength L (in meters) of the waves are related by the equation 2(pi)s^2=9.8L. a. Find the speed the the nearest hundredth of a meter per second of a

4. ### Physics

Two waves traveling on a string in the same direction both have a frequency of 150 Hz, a wavelength of 2 cm, and an amplitude of 0.06 m. What is the amplitude of the resultant wave if the original waves differ in phase by each of