Answer:
D. It has been demonstrated to be without exception under certain stated conditions.
Explanation:
A principle is simply a proposition based on some results from some experiments. A principle becomes a law when it gains strength. That is when other scientists support and back it.
A scientific law is a statement that describes a natural phenomenon and is not contradicted by repeated experiments over the time.
Sir Isaac Newton's law of gravitation stated "A gravitational force exists between all objects in the universe. This force is directly proportional to the masses of the two objects and inversely proportional to the distance between them."
His law explained that every body in the universe attracts every other body. It explained that it is not just Earth that pulls us towards it. But even sun and moon has their own gravitational pull and so does all other objects. It is just that the Gravitational pull of some objects is negligible.
Newton's law of Gravitation is considered a universal law because it is applicable to almost all the bodies in the universe and is demonstrated to be correct for them under certain conditions.
Answer:
d. H + O2 ------ H2O
that's the formation of water
Answer: B. development of female sex
Development of female sex characteristic is not associated with the amount of cortisol in the body.
Explanation:
Cortisol is a steroid hormone secreted by the adrenal gland. It facilitates stress response, regulates blood sugar level and helps fight infections. High cortisol level leads to Cushing syndrome and low cortisol level leads to Addison disease.
Obesity is a symptom of Cushing syndrome while weight loss is a symptom of Addison disease. Thus levels of cortisol can affect body weight as well. When in a stressful situation, our body pumps excess cortisol.
Cortisol level in our body is generally high in the mornings and low in the midnight.
Answer:
amplitude
Explanation:
sound travel and it amplifies
Answer:
The acceleration at the astronaut's head decreases.
Explanation:
Since the centripetal acceleration equals acceleration due to gravity,
a = g = GM/R². since a changes infinitesimally from his foot to his head, we differentiate a with respect to r to get da/dr = -2GM/R³.
So, da, the change in acceleration = -2GMdR/R³ = -2gdR/R = -2 × 9.8/6.4 × 10⁶ m = -3.0625 × 10⁻⁶dR m/s².
Since dR = height of astronaut = 1.80 m, da = -3.0625 × 10⁻⁶ × 1.8 = -5.5125 × 10⁻⁶ m/s².
So the acceleration at the astronaut's head is g + da = 9.8 - 0.0000055125 = 9.7999944875 m/s².
So the acceleration at the astronaut's head decreases.
