Motion, Forces, and Energy

Question

I have a couple questions

- list 3 things that a force can do

-how does mass affect the acceleration rate as something falls

-what causes terminal velocity

-what affect does mass have on the force of gravity

-what affect does distance have on the force of gravity

-how does momentum affect the motion of an object

 

I don't expect answers to all the questions, but a few would be great! Thanks again! 

Answer 1

A force can basically cause an object to speed up, slow down or change direction.  For example, a negative acceleration generally means that the direction of movement has reversed.

 

Acceleration is independent of mass in free fall or projectile motion.  This is because the force due to gravity is constant on all objects.  This is true when air resistance is neglected or when objects are dropped in a vacuum (like outer space).

 

Terminal velocity is the maximum velocity an object experiences in free fall.  Think of it this way: if you jump from an airplane, you speed up as you approach the ground.  However, because of drag (air resistance) this upward force eventually become equal to the force down (weight of the object).  It is at this point that an object is said to reach terminal velocity.  Note that the force down is not mass, but weight so an object's weight will determine the final speed at which terminal velocity is reached.

 

The force of gravity between two objects can be increased by reducing the distance between them. The force of gravity is influenced by the masses of the two objects and the gap between them. Gravitational force generally increases as objects become more massive and draw closer together.

 

An object's mass and momentum are directly related; as mass increases, momentum will have a corresponding increase, assuming a constant velocity. Thus, an object with twice the mass of another object -- moving at the same speed and in the same direction -- will have twice the momentum.