Ask question

Ask question

All categories

3 years ago

5

A transverse, sinusoidal wave travels in a string and can be described by the function: y(x,t)=0.87 sin(21x−4.9t). What is the s

peed of this wave?

1 answer:

pshichka [43]3 years ago

5 0

Answer:

2.61m/s

Explanation:

Given the wave function;

y(x,t)=0.87 sin(21x−4.9t).

The general wave equation is expressed as;

$y = Asin(2\pi ft + 2\pi x /\lambda)$

f is the frequency of the wave

t is the time

$\lambda\\$ is the wavelength

On comparing;

2πft = 4.9t

2πf= 4.9

f = 4.9/2π

f = 4.9/2(3.14)

f = 4.9/6.28

f = 0.78Hz

Get the wavelength;

2πx/ $\lambda$ = 21x

2π/ $\lambda$ = 21

2π = 21 $\lambda$

$\lambda$ = 21/2π

$\lambda$ = 21/2(3.14)

$\lambda$ = 21/6.28

$\lambda$ = 3.34m

Speed = frequency * wavelength

Speed of the wave = 0.78 * 3.34

Speed of the wave = 2.61m/s

Hence the speed of the wave is 2.61m/s

You might be interested in

Irina finds an unlabeled box of fine needles, and wants to determine how thick they are. A standard ruler will not do the job, a

Vsevolod [243]

Answer:

$d=\frac{1.22\times 640\times 10^{-9}\times 21.7}{7.35\times 10^{-2}}=2305.21\times 10^{-7}m$

Explanation:

The expression which represent the first diffraction minima by a circular aperture is given by $d sin\Theta =1.22\lambda$ --------eqn 1

The angle through which the first minima is diffracted is given by $tan\Theta =\frac{y_1}{D}$ ---------eqn 2

As $\Theta$ is very small so we can write $sin\Theta =tan\Theta$

So from eqn 1 and eqn 2 we can write

$y_1=\frac{1.22\lambda D}{d}$ --------eqn 3

Here $y_1$ is the position of first maxima D is the distance of screen from the circular aperture d is the diameter of aperture

It is given that diameter of circular aperture is 14.7 cm so $y_1=\frac{14.7}{2}=7.35 \ cm$

Now putting all these value in eqn 3

$d=\frac{1.22\lambda D}{y_1}$

$d=\frac{1.22\times 640\times 10^{-9}\times 21.7}{7.35\times 10^{-2}}=2305.21\times 10^{-7}m$

8 0

3 years ago

Two atoms that are isotopes will have a different number of what

BigorU [14]

Answer:

different number of mass numbers.

Explanation:

isotopes are atoms of the same element having the same atomic number but different mass numbers due to different number of neutrons.

7 0

3 years ago

A projectile of mass 6.8 kg kg is shot horizontally with an initial speed of 14.5 m/s from a height of 26.7 m above a flat deser

sleet_krkn [62]

Answer:

Explanation:

Given

mass of projectile $m=6.8\ kg$

initial horizontal speed $u_x=14.5\ m/s$

height $h=26.7\ m$

Considering vertical motion

velocity gained by projectile during 26.7 m motion

$v^2-u^2=2 as$

v=final velocity

u=initial velocity

a=acceleration

s=displacement

$v^2-(0)^2=2\times (9.8)\times (26.7)$

$v=\sqrt{523.32}$

$v=22.87\ m/s$

Horizontal velocity will remain same as there is no acceleration

final velocity $v_{net}=\sqrt{(v)^2+(u_x)^2}$

$v_{net}=\sqrt{733.57}=27.08\ m/s$

Initial kinetic Energy $K_i=\frac{1}{2}mu_x^2$

$K_i=\frac{1}{2}\times 6.8\times (14.5)^2=714.85\ J$

Final Kinetic Energy $K_f=\frac{1}{2}mv_{net}^2$

$K_f=\frac{1}{2}\times 6.8\times (27.08)^2$

$K_f=2493.30\ J$

Work done by all the force is equal to change in kinetic Energy of object

Work done by gravity is $W_g$

$W_g=\Delta K$

$W_g=2493.30-714.85=1778.45\ J$

8 0

3 years ago

TAKING 100 PONTS!!! PLEASE SOMEONE HELP.JUST LOOK THE PICTURE

SVETLANKA909090 [29]

Explanation:

oh no i hope i dont fall and the i agree with the other dude

8 0

3 years ago

Read 2 more answers

An unknown mineral is scratched by a penny. It must _____.

Tanya [424]

The answer is a I think

8 0

3 years ago

Read 2 more answers