Lay a pencil on a flat surface. This will serve as the fulcrum for your experiment. 2. Set the center of the ruler on the pencil so that the length of the ruler is perpendicular to the pencil 3. Place stack of 3 pennies onto one end of the ruler. Record the distance from the center of the ruler that these pennies were placed. The distance is from the center of the stack of pennies to the center of the ruler. 4. Predict the distance from the fulcrum that you must place the center of mass of 4, 5, 6, 7 and 8 penny stacks to balance the ruler. You wi

wavelength variability is the right one

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explanation:

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air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.