To solve the problem, it is necessary the concepts related to the definition of area in a sphere, and the proportionality of the counts per second between the two distances.
The area with a certain radius and the number of counts per second is proportional to another with a greater or lesser radius, in other words,


M,m = Counts per second
Our radios are given by



Therefore replacing we have that,






Therefore the number of counts expect at a distance of 20 cm is 19.66cps
Explanation:
speed of wave
v = wavelength x frequency
since frequency is f = 1/Period then
v = wavelength : Period
v = 10 cm/ 0.2 s = 50 cm/s
v = 0.5 m/s
Answer:
hyoid bone
Explanation:
Woodpeckers have a special bone that acts like a seat-belt for its skull. It's called the hyoid bone, and it wraps all the way around a woodpecker's skull. Every time the bird pecks, the hyoid acts like a seat-belt for the bird's skull and the delicate brain it protects.
Its breathing that is moving it is digesting and