Answer:
A. The speed of the wave increases four times.
Answer:
Wavelength, 
Frequency, 
Explanation:
We need to find the intensity of the radiation is a maximum for a black body at 298 K. It can be calculated using Wein's displacement law. It is given by :


Here, T = 298 K


If f is the frequency of black body radiation. It is given by :



Hence, this is the required solution.
1. They could have different types of sounds, so wave-shape could be different.
2. If they have the same frequency, the volume is different, so they could have different amplitudes (larger amplitude = larger sound).
3. Different frequencies based on the pitches
Let's call a the acceleration of the system. The problem says that the block m3 is static, so the acceleration is zero: a=0.
Calling

the tension of the string between m1 and m3, and

the tension of the string between m2 and m3, the problem can be solved by writing the following system of equations:



However, we know that a=0 and the problem asks only for

, so we just need to solve the first equation:

and so
Answer:
A) its internal (thermal) energy does not change.
Explanation:
When a fixed amount of ideal gas goes through an isothermal expansion