<u>Harmful</u><u />
-causes heat; if it's not used correctly, it can cause injury
-when falling, the friction between your knee/leg and the ground can cause scrapes
<u>
</u><u>Helpful</u><u />
-helps stop the bike, the brakes rub against the tire which slows it down to a stop
-it can also help move the bike; the chains rub against tires which accelerate the bike
Here's the formula for the distance covered by an accelerating body in some amount of time ' T '. This formula is incredibly simple but incredibly useful. It pops up so often in Physics that you really should memorize it:
D = 1/2 a T²
Distance = (1/2)·(acceleration)·(time²)
This question gives us the acceleration and the distance, and we want to find the time.
(9,000 m) = (1/2) (20 m/s²) (time²)
(9,000 m) = (10 m/s²) (time²)
Divide each side by 10 m/s²:
(9,000 m) / (10 m/s²) = (time²)
900 s² = time²
Square root each side:
<em>T = 30 seconds</em>
If he is jumping you are adding force which means that you will be falling twice as fast
You used density, because water/ice has a density of 1, and ice will sink in anything with a lesser density
Most geologists accept radiometric dating techniques as valid because radioactive elements decay at a constant and measurable rate.
Answer: Option C
<u>Explanation:</u>
Scientists prefer radioactive dating to carbon dating because it is more accurate in measuring. The analysis depends upon the radioactive decay of radioactive isotopes of any matter in a given rock or soil.
The parent atoms and daughter atoms are compared while studying, and hence age can be calculated easily. Radioactive decay depends upon the given half-life of the atom, which is a constant and is known. So, it would be very easy to calculate the number of progeny atoms and parent atoms and find out their age.
