Answer:
Explanation:
The stored elastic energy in the spring helps the box to rise to a height of .75 m
So stored elastic energy = potential energy attained
1/2 k d² = mgh , k is spring constant , d is compression in spring , m is mass of box , h is height attained .
Putting the values
.5 x 220 x d² = 4 x 9.8 x .75
d² = .2673
d = .517 m
51.7 cm .
AC reverses the current in periods, and the current flows in 2 directions.
DC only flows in one direction and is constant.
AC is typically used to transfer power over long distances from a generator to your home, stepping it up after it's generated to send it over the distance, then stepping it back down so that it is usable in your home.
DC is used typically inside of devices, as it sends a certain amount of electricity through the wires.
Nicolas Tesla, was ripped off by Edison to replace his DC stations with AC instead. ^^
<span>Is more than one displacement possible?
No, displacement only considers the initial and final position.
Is more than one average velocity possible?
No, the average velocity is defined as displacement per time and since there is only one displacement possible, there is only one average velocity possible as well.
Is more than one average speed possible?
Yes, the average speed considers the total distance traveled and this distance may not be the same as the total displacement.
</span>
Answer:
6 km/h west
Explanation:
During part c of the hike, the hiker moved 6 km west, and the time was 9.45 am to 10.45 am.
So, we have:
- displacement: d = 6 km west
- time taken: from 9.45 am to 10.45 am = 1 hour
Therefore, the average velocity is given by the ratio between displacement and time taken:
and the direction is the same as the displacement (west)
A light ray in air enters and passes through a block of glass , the speed will remain same after it emerges from the block
When a light ray enters into the glass then the speed of the light will get decreased because as a light ray enters into a denser medium , the speed of light get decreased . But when the light ray emerges out from glass , it going from denser to rarer medium , due to which speed will increase and come to same value as it was while entering the glass .
To learn more about denser medium here :
brainly.com/question/13613040
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