Let's use the mirror equation to solve the problem:
where f is the focal length of the mirror,
the distance of the object from the mirror, and
the distance of the image from the mirror.
For a concave mirror, for the sign convention f is considered to be positive. So we can solve the equation for
by using the numbers given in the text of the problem:
Where the negative sign means that the image is virtual, so it is located behind the mirror, at 8.6 cm from the center of the mirror.
Answer:
The correct answer would be Saturn's Cassini Division.
Explanation:
Read about it here.
https://caps.gsfc.nasa.gov/simpson/kingswood/rings/
Hope this helps! :)
Answer:at 21.6 min they were separated by 12 km
Explanation:
We can consider the next diagram
B2------15km/h------->Dock
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B1 at 20km/h
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V
So by the time B1 leaves, being B2 traveling at constant 15km/h and getting to the dock one hour later means it was at 15km from the dock, the other boat, B1 is at a distance at a given time, considering constant speed of 20km/h*t going south, where t is in hours, meanwhile from the dock the B2 is at a distance of (15km-15km/h*t), t=0, when it is 8pm.
Then we have a right triangle and the distance from boat B1 to boat B2, can be measured as the square root of (15-15*t)^2 +(20*t)^2. We are looking for a minimum, then we have to find the derivative with respect to t. This is 5*(25*t-9)/(sqrt(25*t^2-18*t+9)), this derivative is zero at t=9/25=0,36 h = 21.6 min, now to be sure it is a minimum we apply the second derivative criteria that states that if the second derivative at the given critical point is positive it means here we have a minimum, and by calculating the second derivative we find it is 720/(25 t^2 - 18 t + 9)^(3/2) that is positive at t=9/25, then we have our answer. And besides replacing the value of t we get the distance is 12 km.
A. Picking up sound waves is the stage of listening that most people refer to as hearing.
<h3>
What is hearing?</h3>
Hearing, or auditory perception, is the ability to perceive sounds through an organ, such as an ear, by detecting vibrations as periodic changes in the pressure of a surrounding medium.
During learning process, when someone picks up the sound waves directed to him/her, it is known as the act of hearing,
Thus, picking up sound waves is the stage of listening that most people refer to as hearing.
Learn more about hearing here: brainly.com/question/14185060
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