Answer:
The absorption lines will shift to the red (become longer).
This is because of the extra distance that a wavelength λ must travel between the vibrations of the source producing the spectrum.
Note that the Doppler effect of the source is slightly different for light waves than it is for sound waves because sound waves require a medium in which to travel while light waves do not require such a medium (example air).
Magnification is the ratio of the image's height to object's height or the ratio of image distance to object distance.
That is; Magnification = height of the image/height of object= image distance/object distance
= x/4 = 21/8
x = (21 × 4)/8
= 10.5 cm
The height of the image is 10.5 cm
The mirror in this case is a concave mirror, since when the object is placed between the principal focus and the concave mirror, it forms a virtual magnified image on the other side ofthe mirror (that is why we have a negative image distance).
Missing question: "<span>At what time is the velocity again zero?"
Solution:
the acceleration of the particle is
</span>
<span>the velocity of the particle is the derivative of the acceleration:
</span>
<span>where </span>
is the initial velocity, given by the problem.
So, to find when the particle's velocity is again zero, we should just put vx=0 and find t:
which has two solutions:
t=0 (beginning of motion)
and so, the particle velocity returns to zero after 20 seconds.
Answer:
<em>d. She will be slightly lower than you but moving upward toward you</em>.
Explanation:
Since your swing is slightly shorter than your friend's swing, then you will have more angular speed than your friend. Angular speed increases with a decrease in radius. The closer the body is to the center, the faster the body swings. By the time you would have completed one complete swing back and forth, your friend will just be moving towards you, and she will be slightly lower than you but moving upwards towards you. This principle is the same reason gymnasts pull their limbs closer to their body when they need to swing faster.
Answer:
100 times
Explanation:
The light gathering power is the ability of a telescope to accumulate plenty of light than the human eye.
The area of the objective lens is given by:
Circular area= pi × diameter/4
Given diameter of telescope =60mm
Diameter of human eye =6mm
3.142×60^2/4 ) ÷ (3.142×6^2/4)
Cancelling pi out leaves
(3600/4)÷(36/4)
900/9 =100 times