Answer:
The hypothesis may or may not be true and needs to be tested. It might be the answer to the problem. Hence, it must be tested thoroughly. When these predictions are tested again and again in independent scientific experiments and gets verified, the hypothesis is converted into a scientific theory.
Divide the distance traveled by the time it took:
(100 m) / (4.2 s) ≈ 23.8 m/s
Answer: 14.28 m/s
Explanation:
Assuming the girl is spinning with <u>uniform circular motion</u>, her centripetal acceleration 
is given by the following equation:
(1)
Where:
is the <u>centripetal acceleration</u>
is the<u> tangential speed</u>
is the <u>radius</u> of the circle
Isolating from (1):
(2)
<u />
Finally:
This is the girl's tangential speed
Potential energy is highest when the car is released at the top of the ramp. The correct answer is option C
Potential energy is the energy possessed by a body when the body is at rest. Potential energy is at time called gravitational potential energy which as a product of mass of the body, acceleration due to gravity and the height attained by the body. That is,
P.E = mgh
When a car is moving down a ramp, the potential energy of the car can never remain the same except the car stop at a certain point.
Whenever a car is moving down a ramp, the potential energy of the car will be highest when the car is release at the top of the ramp. And lowest when the car reaches the bottom of the ramp.
The statement that is correct about the potential energy of a car moving down a ramp is:
Potential energy is highest when the car is released at the top of the ramp.
Therefore, the correct answer is option C
Learn more here: brainly.com/question/17400615
<h2>
Answer: dark matter</h2>
It is believed that the Milky Way has 90% dark matter and only 10% ordinary matter (known matter). Because, like gravity, <u>dark matter can not be observed directly</u>, however its existence is inferred through the movement of the stars and the cosmic dust within the galaxy.
It is important to note that dark matter composition is unknown and corresponds to 80% of the matter in the universe. It does not emit or interact with any type of electromagnetic radiation, but it interacts with the known matter through gravity.
