Answer:
<u>Chemical changes</u> are recognized when a substance changes its properties permanently and it cannot be the same substance as before.
Instead the<u> physical changes</u><u> </u>implies that if you can return to the same substance through a reverse process.
Explanation:
A chemical change is, by example, a combustion, if a sheet of paper burns, its result is ashes, the ashes cannot go back to being a sheet of paper because its properties changed, heat energy was generated that changed matter permanently.
A physical change, by example, is that of freezing water, the water becomes ice, but this can easily become water again if the temperature is increased, its properties do not change and the chemistry of the substance does not change.
Answer:
If the height is in metres, the speed is 24.25m/s
Object Motion: 25 m/s
Circumference of Circle:
1/4 Circumference of Circle in 1 second = 25 meters
25 meters times 4 = Circumference of Circle
Circumference = 100 meters
Formula to Find Circumference of Circle: (work opposite)
C = 2<span>πr
100 = </span>2πr divided
100/2π = r simplify
50/π = r (exact radius)
Answer:
50/π meters = r (exact radius)
