Answer:
Frequency, 
Explanation:
Given that,
The wavelength of the x-rays, 
We need to find the frequency of an x-ray. All electromagnetic wave travel with a speed of light. It is given by the formula as :

f is the frequency

So, the frequency of an x-ray is
. Hence, this is the required solution.
Answer:
Divide by 3
Explanation:
In order to estimate the distance traveled by a lightening flash in kilometers, we follow these simple steps:
- Make a count of the number of seconds in between the period a flash occur and the thunder accompanied by the lightening flash is heard.
- Dive the total number of seconds by 3 to get the distance traveled by the flash. This is because in order to cover 1 km, it roughly takes 3 seconds.
<span>GPE= mgh = 0.1 kg * 9.8 m/s^2 * 12.5m = 12.25 J</span>
There will not be enough momentum from the first hill to cross another hill if he same or larger size because of the way potential energy and kinetic energy works it will not be able go as high as it could go on he fist hill.
Answer:
a

b

Explanation:
From the question we are told that
The speed of the spaceship is 
Here c is the speed of light with value 
The length is 
The distance of the star for earth is 
The speed is 
Generally the from the length contraction equation we have that
![l = l_o \sqrt{1 -[\frac{v}{c } ]}](https://tex.z-dn.net/?f=l%20%20%3D%20%20l_o%20%20%5Csqrt%7B1%20-%5B%5Cfrac%7Bv%7D%7Bc%20%7D%20%5D%7D)
Now the when at rest the length is 
So



Considering b
Applying above equation
![l =l_o \sqrt{1 - [\frac{v}{c } ]}](https://tex.z-dn.net/?f=l%20%20%3Dl_o%20%5Csqrt%7B1%20-%20%20%5B%5Cfrac%7Bv%7D%7Bc%20%7D%20%5D%7D)
Here 
So


