Answer:
The wavelength of wave is 7.5 meter.
Given:
Speed of wave = 1500 
Frequency of wave = 200 Hz
To find:
Wavelength of wave = ?
Formula used:

Where
= wavelength of the wave
v = speed of wave
n = frequency of wave
Solution:
Wavelength of wave is given by,

Where
= wavelength of the wave
v = speed of wave
n = frequency of wave

= 7.5 m
The wavelength of wave is 7.5 meter.
Answer:
0.786 Hz, 1.572 Hz, 2.358 Hz, 3.144 Hz
Explanation:
The fundamental frequency of a standing wave on a string is given by

where
L is the length of the string
T is the tension in the string
is the mass per unit length
For the string in the problem,
L = 30.0 m

T = 20.0 N
Substituting into the equation, we find the fundamental frequency:

The next frequencies (harmonics) are given by

with n being an integer number and f being the fundamental frequency.
So we get:



Answer:
The mass of the earth, 
Explanation:
It is given that,
Time taken by the moon to orbit the earth, 
Distance between moon and the earth,
We need to find the mass of the Earth using Kepler's third law of motion as :




So, the mass of the earth is
. Hence, this is the required solution.
Answer:
9241.6 W or 12.39318 hp
Explanation:
u = Initial velocity = 0
v = Final velocity
m = Mass
t = Time taken
Energy

Power

Converting to hp


The power developed by the cheetah is 9241.6 W or 12.39318 hp
1 astronomical unit = 149597870700m
Enrico should divide distance in meters with this number.