Explanation:
A wave on a string is described is given by :
![D(x,t)=2\ cm\ sin[(12.57\ rad/m)-(638\ rad/s)t]](https://tex.z-dn.net/?f=D%28x%2Ct%29%3D2%5C%20cm%5C%20sin%5B%2812.57%5C%20rad%2Fm%29-%28638%5C%20rad%2Fs%29t%5D)
The linear density of the string is 5 g/m.
Where
x is in meters and t is in seconds
The general equation of a wave is given by :
(2) The speed of the wave in terms of tension is given by :

Also, 
So, 


T = 12.88 N
(3) The maximum displacement of a point on the string is equal to the amplitude of the wave. So, the maximum displacement is 2 cm.
(4) The maximum speed of a point on the string is given by :


v = 12.76 m/s
Hence, this is the required solution.
Answer:
The length of a tube and number of rounds are 0.848 m and
.
Explanation:
Given that,
Wavelength 
m = 160000
We need to calculate the length
Using formula of wavelength
Laser tube behave like closed pipe



Distance traveled by pulse of light in one back and fourth trip



We need to calculate the time
Using formula for time



We need to calculate the number of round
Using formula of number of round



Hence, The length of a tube and number of rounds are 0.848 m and
.
Answer:
-58.8 J
Explanation:
The work done by a force is given by:

where
F is the magnitude of the force
d is the displacement of the object
is the angle between the direction of the force and the displacement.
In this problem, we are asked to find the work done by gravity, so we must calculate the magnitude of the force of gravity first, which is equal to the weight of the object:

The displacement of the object is d = 3.00 m, while
, because the displacement is upward, while the force of gravity is downward; therefore, the work done by gravity is

And the work done is negative, because it is done against the motion of the object.
Time=speed/acceleration
Gravitaional Acceleration=9.8 m/s^2
Speed=24.5 m/s
Time=24.5/9.8=2.5 s