Answer:
15.C Mucus reduces friction
The b<span>ottom one because it has longer wavelengths and because the bottom ones has 3 wavelengths</span>
Stairs don't HAVE any power. When you use the stairs, YOU have to provide all the power. I would use the elevator, because the machinery that runs it produces the power and I only have to stand there.
Answer:
a) the acceleration is -9.8 m/s^2 (gravity's acceleration), the magnitude is 9.8 m/s^2 and the direction is downwards.
The pebble is not decelerating since the magnitude of it's speed is increasing, even if it is on a negative direction.
b) after 0.5 s the pebble is 5.725 meters down. (or -5.725m from it's initial position.)
Explanation:
a) the acceleration is given only by gravity, it's the only force acting on the pebble, the slingshot only gives the pebble an initial speed.
b) To calculate the position we use the equation
y0 + v0·t + ½·g·t² = yf
replacing:
0 + (-9.0m/s) * 0.5s + 1/2 (-9.8)*0.5² = yf
-5.725 = yf
