<span>Answer:
Correct answer is
just add the two kinetic energies;
E = (1/2)mv^2 + (1/2)mv^2</span>
Answer:
black will be hotter because black paint absorbs light and white reflects it.
Answer:
Removing some of the books reduced the mass of the box, and less force was needed to push it across the floor.
<span>The Earth’s internal "((HEAT))" source provides the energy for our dynamic planet, providing it with the driving force for on-going disastrous events such as earthquakes and volcanic eruptions and for plate-tectonic motion. </span>
Answer:
Distance: 21 yd, displacement: 15 yd, gain in the play: 12 yd
Explanation:
The distance travelled by Sam is just the sum of the length of each part of Sam's motion, regardless of the direction. Initially, Sam run from the 3 yd line to the 15 yd line, so (15-3)=12 yd. Then, he run also 9 yd to the right. Therefore, the total distance is
d = 12 + 9 = 21 yd
The displacement instead is a vector connecting the starting point with the final point of the motion. Sam run first 12 yd straight ahead and then 9 yd to the right; these two motions are perpendicular to each other, so we can find the displacement simply by using Pythagorean's theorem:

Finally, the yards gained by Sam in the play are simply given by the distance covered along the forward-backward direction only. Since Sam only run from the 3 yd line to the 15 yd line along this direction, then the gain in this play was
d = 15 - 3 = 12 yd