Unit 3 Blog Post

In Unit Three, many of our topics were focused on and about Force.  We discussed Newton's 3rd Law, Action/ Reaction Pairs, Forces and Vectors, Tides, and Momentum and Impulse.

Newton's 3rd Law

Newton's 3rd Law states that every action has an equal and opposite reaction.  When writing these reactions, called action/reaction pairs, we switch the subject of the sentence,  but keep the verb the same.  Below are some examples.



Also under the category of Newton's 3rd Law is the infamous Horse and buggy problem.  Below is a diagram detailing all of the action/reaction pairs that take place.

Notice that each of the action reaction pairs are equal in force and opposite in direction.  We know this because of Newton's 3rd Law, which states that every action has an equal and opposite reaction.  The Horse and Buggy moves forward because the force between the horse in the ground is greater than the force between the buggy and the ground.  This means that the horse and buggy moves in the horse's direction.

Forces and Vectors



Tensions in ROPES create net force.  The farther apart the rope, th more tension.


Which side of the rope has more tension? Side A or Side B?

The force of gravity creates an "f weight".  To find the tension in the ropes, we recreate the "f weight above the ball, and create lines
parallel to the ropes.  Shown in the green is the tension.  We see that rope B has more tension, as its green line is longer.






The next part of vectors is learning why things slide down hills.
Through the example below, we learn that the box accelerates
down the hill because the the f net downwards.



Tides

Tides occur as a result of the differences in force, as shown below.  The Universal Gravitational Law states that Sides A and B experience different forces.

Tides occur as a result of the moon.  We know that the moon has a larger pull on the earth than the sun because of the Universal Gravitational Formula.






There a couple different kinds of tides.  NEAP tides occur when the Moon is perpendicular to the Sun. SPRING tides occur when the Moon is in line with the Sun.

Momentum and Impulse

Momentum is inertia in motion.  It is represented by the formula "p=mv".  The greater the mass of an object, the greater the momentum.

Impulse is the change in momentum- "(change in p)= J".  It is represented by the formula "J=(F)(change in t)".

The Conservation of Momentum

The Law of Conservation of Momentum states that the amount of momentum is the same before and after an equation.  This is proved by Newton's 3rd law, which states every action has an equal and opposite reaction.

Below is a video that helps to explain Momentum and Impulse, and the Law.