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.
a) we can answer the first part of this by recognizing the player rises 0.76m, reaches the apex of motion, and then falls back to the ground we can ask how
long it takes to fall 0.13 m from rest: dist = 1/2 gt^2 or t=sqrt[2d/g] t=0.175
s this is the time to fall from the top; it would take the same time to travel
upward the final 0.13 m, so the total time spent in the upper 0.15 m is 2x0.175
= 0.35s
b) there are a couple of ways of finding thetime it takes to travel the bottom 0.13m first way: we can use d=1/2gt^2 twice
to solve this problem the time it takes to fall the final 0.13 m is: time it
takes to fall 0.76 m - time it takes to fall 0.63 m t = sqrt[2d/g] = 0.399 s to
fall 0.76 m, and this equation yields it takes 0.359 s to fall 0.63 m, so it
takes 0.04 s to fall the final 0.13 m. The total time spent in the lower 0.13 m
is then twice this, or 0.08s
<span>5. Dry ice is an example of _________, which is the process of a solid turning directly into a gas. (1 point)
sublimation
6. The ____ is a unit of force. (1 point)
</span>n<span>ewton
7. Which of the following is the boiling point of water? (1 point)
100°C
8. Which of the following describes the molecular structure of water at 40°C? (1 point)
water molecules are close together and moving freely around each other </span>
Answer:
T = 20.84°C
Explanation:
From the law of conservation of energy:
Heat Lost by Copper Block = Heat Gained by Aluminum Calorimeter + Heat Gained by Water
where,
= mass of copper = 227 g
= mass of water = 844 g
= mass of aluminum = 155 g
= specific heat capacity of calorimeter = 385 J/kg.°C
= specific heat capacity of water = 4200 J/kg.°C
= specific heat capacity of aluminum = 890 J/kg.°C
= change in temperature of copper = 283°C - T
= change in temperature of water = T - 14.6°C
= change in temperature of aluminum = T - 14.6°C
T = equilibrium temperature = ?
Therefore,
<u>T = 20.84°C</u>
The complete question is as follows: A student is subjected to a reaction force of 10 N northward from a 5 kg block while pushing the block over a smooth, level surface. Ignoring friction, what is the acceleration of the block?
Answer: The acceleration of the block is 
.
Explanation:
Given: Force = 10 N
Mass = 5 kg
It is known that force applied on an object is the product of mass and acceleration.
Mathematically, 
where,
F = force
m = mass
a = acceleration
Substitute the values into above formula as follows.
Thus, we can conclude that the acceleration of block is .
