Explanation:
A wavefront is the long edge that moves, for example, the crest or the trough. Each point on the wavefront emits a semicircular wave that moves at the propagation speed v. These are drawn at a time t later, so that they have moved a distance s = vt.
Systematic is just a certain way of doing something. So science being systematic may just refer to the scientific method or how theories are proved in science by repeating the scientific method over and over again.
The fact that all phones are slightly different but achieve same primary goal tells us about technology that there can be many different design solutions to address a single problem (option D).
<h3>What is technology?</h3>
Technology is the organization and application of knowledge for practical purposes.
According to this question, many different companies have produced cell phones through technological applications. Although all of the phones are slightly different, they all achieve the same primary goal.
This shows us an intriguing aspect of technology that there can be many different design solutions to address a single problem.
Learn more about technology at: brainly.com/question/9171028
#SPJ1
Answer:
B.)Angular momentum is always conserved
Explanation:
Angular momentum is given by:
where
m is the mass of the object
v is its speed
r is the distance between the object and the centre of its circular trajectory
In absence of external torques, angular momentum is always conserved. That means that for the spinning star, if its radius r decreases (because it shrinks), in order for L (the angular momentum) to be conserved, the speed (v) must increases, therefore the spinning star speeds up.
So, the correct choice is
B.)Angular momentum is always conserved
Answer:
A) Polaris, the North star
Explanation:
Polaris, also known as the Pole star or north star, lies almost along the axis of Earth. Because of this Polaris seems to be fixed at one point in the sky while all other celestial objects change their positions in the sky due to rotation of Earth.
Since, it is fixed at one point in the sky in the North direction, explorers used to take help of Polaris to find direction in the night time. Since Polaris is not the brightest star in the night sky (it is 48th brightest star) our ancestors took help of constellations to find it. One of the method was to use Big Dipper of "Ursa Major" constellation. The pointer stars (Merak and Dubhe) of big dipper point towards the Polaris. One can easily spot it in the sky as well.
