Answer:

Explanation:
Δ
- Δ
is the difference in velocity before and after a given time.
is the acceleration of the object during this time.
is time
is another way to write this equation.
- The Δ symbol represents "the difference between the initial and final values of a magnitude or vector", so Δ


- I rearranged this equation to solve for
, but this is a step that you don't need to take, it's just good to get in the habit of doing this. - Plug in the given values. Note that our final velocity is
, because the car travels until at <em>rest</em>.
![a=\frac{v_f-v_i}{t}\\a=\frac{(0)-[(17.1\frac{miles}{hour} )(\frac{hour}{3600s})(\frac{1609.34m}{mile})]}{9.7s}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7Bv_f-v_i%7D%7Bt%7D%5C%5Ca%3D%5Cfrac%7B%280%29-%5B%2817.1%5Cfrac%7Bmiles%7D%7Bhour%7D%20%29%28%5Cfrac%7Bhour%7D%7B3600s%7D%29%28%5Cfrac%7B1609.34m%7D%7Bmile%7D%29%5D%7D%7B9.7s%7D)
- Our initial velocity is in mph, something not in standard units, so if not changed, you will get an incorrect answer. What you need to do is cancel out the units your prior value had using division and multiplication, and at the same time multiply and divide the correct numbers and units into your equation. Or look up a converter.
![a=\frac{(0)-[(17.1\frac{miles}{hour} )(\frac{hour}{3600s})(\frac{1609.34m}{mile})]}{9.7s}\\a=\frac{0m/s-7.6m/s}{9.7s} \\a=\frac{-7.6m/s}{9.7s}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7B%280%29-%5B%2817.1%5Cfrac%7Bmiles%7D%7Bhour%7D%20%29%28%5Cfrac%7Bhour%7D%7B3600s%7D%29%28%5Cfrac%7B1609.34m%7D%7Bmile%7D%29%5D%7D%7B9.7s%7D%5C%5Ca%3D%5Cfrac%7B0m%2Fs-7.6m%2Fs%7D%7B9.7s%7D%20%5C%5Ca%3D%5Cfrac%7B-7.6m%2Fs%7D%7B9.7s%7D)
- if you converted correctly, your answer for
will be ≅
. - Now divide. Notice that the units for acceleration are
or <em>meters per second, per second</em>.

- Our final answer is <em>negative </em>because the car is <em>slowing down</em>. Do not square this answer as the square symbol only applies to the units, not the magnitude.
Answer:
Noise cancelling headphones have a microphone which listens to the ambient noise. The headphone then processes the sound and provides a wave to produce destructive interference. This cancels the ambient noise.
Explanation:
First, let us understand what interference is. Interference is the phenomenon that occurs when two waves superpose to form a wave which has a different wavelength, frequency, amplitude than the original two waves. When the crest of one wave superposes with the other waves crest then this results in the amplitude increasing. This is known as constructive interference. When the crest of one wave superposes with the other waves trough then this results in the amplitude decreasing. This known as destructive interference.
Noise cancelling headphones have a microphone which listens to the ambient noise. The headphone then processes the sound and provides a wave to produce destructive interference. This cancels the ambient noise.
Answer:
reflection is the act of reflecting or the state of being reflected while echo is
reflection of sound waves from a surface back to the initial listener
Answer:
Main Asteroid Belt: The majority of known asteroids orbit within the asteroid belt between Mars and Jupiter, generally with not very elongated orbits. The belt is estimated to contain between 1.1 and 1.9 million asteroids larger than 1 kilometer (0.6 mile) in diameter, and millions of smaller ones.
Explanation:
Answer:
A sloping surface separating air masses that differ in temperature and moisture content is called a front.