Answer:
option D
Explanation:
Sunspots are the spot that appears on the sun, this spot appears darker than the surrounding surface of the sun.
Sun magnetic field goes through a cycle and this cycle is called the Sunspot cycle. Every 11 years the magnetic field of the sun completely flips. This sunspot cycle affects activity on the surface of the sun.
Sunspot cycle is the pattern of solar activity where an average number of sunspot gradually increase and decrease.
Hence, the correct answer is option D
Answer:
= 391.67 Hz
Explanation:
The sound of lowest frequency which is produced by a vibrating sting is called its fundamental frequency ().
The For a vibrating string, the fundamental frequency () can be determined by:
= 
Where v is the speed of waves of the string, and L is the length of the string.
L = 42.0 cm = 0.42 m
v = 329 m/s
= 
= 
= 391.6667 Hz
The fundamental frequency of the string is 391.67 Hz.
Pressure is defined as force per area.
It is normally further advantageous to apply pressure preferably than force to explain the importance toward liquid reaction.
Your question: The strong nuclear force felt by a single proton in a large nucleus _______________________.
Answer: is about the same as that felt by a single proton in a small nucleus.
Answer:
The radius of the wetter area expands at a rate of 
milimeters per second when radius is 150 milimeters.
Explanation:
From Geometry we remember that area of a circle is described by this expression:
(Eq. 1)
Where:
- Radius of the circle, measured in milimeters.
- Area of the circle, measured in square milimeters.
Then, the rate of change of the area in time is derived by concept of rate of change, that is:
(Eq. 2)
Where:
- Rate of change of radius in time, measured in milimeters per second.
- Rate of change of area in time, measured in square milimeters per second.
Now the rate of change of radius in time is cleared within equation above:
If we know that 
and 
, then the rate of change of radius in time is:
![\frac{dr}{dt} = \left[\frac{1}{2\pi\cdot (150\,m)} \right] \cdot \left(4\,\frac{mm^{2}}{s} \right)](https://tex.z-dn.net/?f=%5Cfrac%7Bdr%7D%7Bdt%7D%20%3D%20%5Cleft%5B%5Cfrac%7B1%7D%7B2%5Cpi%5Ccdot%20%28150%5C%2Cm%29%7D%20%5Cright%5D%20%5Ccdot%20%5Cleft%284%5C%2C%5Cfrac%7Bmm%5E%7B2%7D%7D%7Bs%7D%20%5Cright%29)
The radius of the wetter area expands at a rate of milimeters per second when radius is 150 milimeters.
