Answer:
The result is a vector perpendicular to the xy plane: 23.38 k
Explanation:
The cross product of two vectors r and s is defined only in three-dimensional space and is denoted by r × s. The cross product is defined by the formula:
r × s =║r║·║s║· Sin θ· n
where θ is the angle between r and s in the plane containing them, ‖r‖ and ‖s‖ are the magnitudes of vectors r and s, and n is a unit vector perpendicular to the plane containing a and b in the direction given by the right-hand rule.
So, the result is:
r × s = 4.40 * 7.45 * Sin (134.5°) k = 23.38 k
Answer: Option B: They don't understand how redshifts affects stars.
There are millions and billions of stars in our universe. Scientists study stars using telescopes. But some stars are so far, that even the best powerful telescopes are not able to detect their light. Also, the interstellar distance is filled with clouds of dust and gas which makes some part of the universe opaque. It becomes difficult to study stars using earth based telescopes due to lot of light pollution. Astronomers understand how redshifts affects stars and hence, are able use this to study stars via their spectrum. Hence, astronomers don't understand how redshifts affects stars is a wrong reason of why they face difficulty in looking at distant stars.
Answer: please find the answer in the explanation
Explanation:
Sound wave is a mechanical wave that requires a medium for its propagation. For sound to be produced, you will need a vibrating device or object. Anything that can vibrate. Such as tuning fork, membrane, vibrating skin, etc.
After that, you will need a medium in which the sound will be propagated. Air for instance.
And finally, a device that can record ot trap the produced sound.
by changing the frequency of standing waves
