Tuesday, 1 November 2011

Newton's Third and Best Law of Motion

  • First of all, we got our quizzes back that we wrote unexpectedly on Friday then we learned about Newton's third law of motion which states: For every action force there exists a reaction force that is equal in magnitude but opposite in direction.
  • After that we really didn't do much except a few examples on the third law of motion using F=ma and stating what the action or reaction was from an object doing something.
Ex: Badminton racquet hitting a birdie.
  • Action: racquet force to birdie.
  • Reaction: birdie applying force to the racquet.
Ex: Three toboggans are connected by a weightless, steel rope. The first toboggan has a mass of 75kg, the 2nd has a mass of 55kg, and the 3rd has a mass of 10.0kg. If the force exerted on the first toboggan is 310N and surfaces are considered to be frictionless, Find:

a) The acceleration of the toboggans.

F=ma changing the formula to a=f/m to find the acceleration. So it will be: a=310N/140Kg
=2.2m/s^2[E]

b) the force exerted by the toboggan two on toboggan three.

Again, F=ma in which F = ?, m = 10KG, and a = 2.2m/s^2 [E]
Therefore: F=(10KG)(2.2m/s^2[E])
=22N

c) the force exerted by toboggan one on toboggan two.

We will find out the true answer for this today in class, hopefully.

Blake is next.

No comments:

Post a Comment