Answer:
The answer is D.
Explanation:
One explanation I can give you is that generally waves travel faster through denser medium because the particles are tightly packed together and so they can transfer energy faster. But to verify the answer, I used Process of Elimination because the other 3 answers are not true. Choice A is entirely true, wave speed depends on the medium it is travelling through, so there is no way choice A is correct. Choice B is wrong because for example if we take light(an EM wave), it travels at a constant speed of 3.0x10^8 m/s in a vacuum and in open space. So, that proves that air or vacuum do not affect the speed of the wave in another medium. Choice C is related to Choice B, we just proved the speed of light is constant everywhere whereas choice C says that in a vacuum the speed is halved. Good luck in your Physics class and I hope for your best!
Answer:
1 A, 3 B, and 7 A are examples of <em>group number</em> on the periodic table.
Explanation:
The table that consists of elements arranged systematically on the basis of atomic numbers is called periodic table. Groups and periods are two important part of a periodic table. A periodic table contains seven horizontal rows, called as periods and 18 vertical columns, called group.
The groups name is given in the form of number and alphabets. It represents the columns present in the periodic table.
Hence, 1 A, 3 B, and 7 A are examples of <u><em>group number</em></u> on the periodic table.
Answer:
While In an <em><u>ideal/isolated</u></em> system, as long as the object is not in motion, its potential energy will be the same.
However, <u>potential energy is relative</u>. On Earth, usually, it is measured with respect to gravity. <u>The higher the object, the greater the potential gravitational energy</u>. It's all relative. For the sake of this question, I would assume that potential energy increases.
Explanation:
While kinetic energy depends upon speed, potential energy is always relative to some arbitrary reference point.
Source https://www.physicsforums.com/threads/potential-energy-kinetic-energy.11481/
Answer:

Explanation:
When the velocity changes uniformly, the object has a constant acceleration. The acceleration, the velocities, and the distance are related by the equation:

Where:
vf = final velocity
vo = initial velocity
a = acceleration
x = distance
Solving for a:

The car travels a distance of x=200 m and the velocities are:
vo = 216 Km/h
vf = 360 Km/h
Both velocities must be converted to meters by seconds.
vo = 216 Km/h *1000/3600 = 60 m/s
vf = 360 Km/h *1000/3600 = 100 m/s
The acceleration is:




<span>The density of the energy that is transported under the waves under the ocean surface is about five times higher compared to the wind energy 20 meter (about 65 feet) above. In other words, the amount of energy in a single wave is very high. However it turns out that when they tried to make the high power of the waves to power things in a house it only made it past the first few stages there were very few that made it to some stages. This started taking place in around 2001. hope this helped if not let me know and i could explain more:)
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