The correct answer is
Air resistance
In fact, when a ball is in free fall, there are two forces acting on it:
- its weight (force of gravity), acting downward
- the air resistance, acting upward
The effect of the weight is to accelerate the ball, because its direction is the same as the direction of motion of the ball, while the effect of the air resistance is to slow down the ball, because its direction is opposite to that of the motion.
A group of students toured a limestone cave in northwest Georgia.
Which of these best explains how the limestone caves in Georgia were formed?
A. Plant roots split the rock.
B. Acidic water dissolved the rock.
C. Animals burrowed into the rock.
D. Ice formed and broke up the rock.
Answer:
5 meters per second
Explanation:
5m is the distance
5m west is the vector
5m per second is the velocity
5m per second west is unknown
Current electricity is caused by flowing negatively charged particles.
Power = work done/time. Work done by gravity = mgh = 45x9.8x3.2 = 1411.2J. Therefore, power = 1411.2/2 = 705.6 ~ 706W.