4. 540 Kilometers
5. 200 s
Answer:

Explanation:
Given:
Length of a rope,
Position of Canary on the rope from one end, 
Position of Grackle on the rope from another end, 
Tension in the rope, 
linear mass distribution on the rope, 
We have for the speed of wave on the string:



<em>For canary to be undisturbed we need a node at this location.</em>
<em>Also, at the end close to Canary there must be a node to avoid any change in pattern of vibration.</em>
So,
the distance between Canary and the closer end must be equal to half the wavelength.


∴Wavelength of wave to be produced = 20 m. This will give us nodes at the multiples of 10 and anti-nodes at the multiples of 5.
Now, frequency:



Answer:
94.82 nm
Explanation:
We have given that wavelength 
We have to find the minimum film thickness that produces the least reflection
minimum thickness is given by 
here n is given n=1.45
so minimum thickness 
so the minimum film thickness will be 94.82 nm
When a satellite is revolving into the orbit around a planet then we can say
net centripetal force on the satellite is due to gravitational attraction force of the planet, so we will have


now we can say that kinetic energy of satellite is given as


also we know that since satellite is in gravitational field of the planet so here it must have some gravitational potential energy in it
so we will have

so we can say that energy from the fuel is converted into kinetic energy and gravitational potential energy of the satellite
Explanation:
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