Melatonin is a hormone being produced by small gland in the brain called pineal
gland that helps control sleep and wake cycles. It is also called the sleep
hormone because it gives signal that it’s time to sleep. People
also used this hormone to adjust the body’s internal clock. It is the hormone
that released in response to exposure to sunlight. When the sun sets and night
falls, the pineal is activated and begins to vigorously produce melatonin. The
amount of melatonin tends to rise as night falls, peaks at midnight, and falls
again as the sun rises. It means that it produced more when darker and when the
lighter it is; the less melatonin is produced.
Answer:
Th e correct answer is B. Balance
Explanation:
Balance is an ability of a body to maintain the line of gravity with negligible postural sway. Sway is the horizontal movement of the center of gravity of a body if a body is standing still.
If you want to stay for a long period of time in one position without movement, then you need balance. So the term refers to the use of strength to hold the body's position is balance.
Agility refers to the flexibility of the body or jumping
Power means Strength in general
Speed is the ability that how can a person run fast.
To solve this problem we must basically resort to the kinematic equations of movement. For which speed is defined as the distance traveled in a given time. Mathematically this can be expressed as

Where
d = Distance
t = time
For which clearing the time we will have the expression

Since we have two 'fluids' in which the sound travels at different speeds we will have that for the rock the time elapsed to feel the explosion will be:


In the case of the atmosphere -composite of air- the average speed of sound is 343m / s, therefore it will take


The total difference between the two times would be


Therefore 3.357s will pass between when they feel the explosion and when they hear it
Answer:
r = 2,026 10⁹ m and T = 2.027 10⁴ s
Explanation:
For this exercise let's use Newton's second law
F = m a
where the force is electric
F =
Acceleration is centripetal
a = v² / r
we substitute
r =
(1)
let's look for the charge in the insulating sphere
ρ = q₂ / V
q₂ = ρ V
the volume of the sphere is
v = 4/3 π r³
we substitute
q₂ = ρ
π r³
q₂ = 3 10⁻⁹
π 4³
q₂ = 8.04 10⁻⁷ C
let's calculate the radius with equation 1
r = 9 10⁹ 1.6 10⁻¹⁹ 8.04 10⁻⁷ /(9.1 10⁻³¹ 628 10³)
r = 2,026 10⁹ m
this is the radius of the electron orbit around the charged sphere.
Since the orbit is circulating, the speed (speed modulus) is constant, we can use the uniform motion ratio
v = x / t
the distance traveled in a circle is
x = 2π r
In this case, time is the period
v = 2π r /T
T = 2π r /v
let's calculate
T = 2π 2,026 10⁹/628 103
T = 2.027 10⁴ s