Wednesday, December 3, 2014 By the end of the day today, IWBAT… Calculate force using Newton’s 2 nd Law By the end of the day today, IWBAT… Calculate force using Newton’s 2 nd Law Do Now: Do Now: The diagram to the left is called a ___________. If the net force on this object is 40 N right, A = ? B = ? A B 100 N 40 N

Assignment  Read Newton’s Second Law of Motion (pgs ) in the textbook. Take Cornell Notes on the subject matter.  Essential Question: How are the mass, acceleration, and force of an object related  Summary- Ques 1-4 pn pg. 99.

Bellringer  Calculate the overall Net Force for both figures to the left.  Figure 1?  Figure 2?

Why it matters in LIFE: Newton’s Laws explain why you always should wear a seatbelt! Why it matters in LIFE: Newton’s Laws explain why you always should wear a seatbelt! Why it matters in THIS CLASS: This is a HUGE topic that will not only help us reach our goal of 85%, but will also be test on the TAKS test in April Why it matters in THIS CLASS: This is a HUGE topic that will not only help us reach our goal of 85%, but will also be test on the TAKS test in April By the end of the day today, IWBAT… Calculate force using Newton’s 2 nd Law By the end of the day today, IWBAT… Calculate force using Newton’s 2 nd Law

What it might look like on a test: If a woman has a mass of 60 kg (mass), what is her weight on earth in Newtons? Bellringer

Agenda Do Now5 min Legend of the Week5 min Quick Note5 min FBD + Newton’s 1 st Law Quizzes 15 min Newton’s 2 nd Law20 min

Wednesday, 12/3/14 NGS Standard: Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration. By the end of today, IWBAT… Calculate force using Newton’s 2 nd Law How are the mass, acceleration, and force of an object related Topic: Newton’s 2 nd Law Put this into your table of contents!

Newton’s Second Law of Motion  An object’s acceleration depends on its mass and the force applied to it force Force = mass x acceleration F = m x a When force is constant…  Greater mass = slower acceleration (Inversely Proportional)  Smaller mass = greater acceleration (Inversely Prop.)

Example  If 2 objects are pushed with the same force, which would have the greater acceleration? m = 0.5g m = 14 g

How does mass effect inertia?  The greater the mass of an object, the greater the net force required to get it moving or to change its motion Which has the most inertia?

Example  What is the force of a truck if it has a mass of 100 kg and an acceleration of 10 m/s2?  Given: Mass = 100 kg, acceleration = 10 m/s 2  Unknown: Force?  Equation: Force= mass x acceleration (F= m x a)  Substitute: Force = 100 kg x 10 m/s 2  Solve: 1000 kg  m/s 2

Question?  1000 kg  m/s 2 ?  What did we learn the unit for force was?  Newton (N) = kg  m/s 2

Group Practice Net ForceMassAcceleration 10 N2 kg? 20 N2 kg? 20 N4 kg? ?2 kg5 m/s2 10 N?10 m/s2 Based on the table above, what relationships do you see between force, mass, and acceleration?

Mass vs. Weight  Mass: quantity dependent on the amount of matter present in an object  Units = kg  MASS NEVER CHANGES  Weight: the FORCE of gravity with which Earth attracts an object towards itself  Units = N  WEIGHT DEPENDS ON GRAVITY  EARTH’S GRAVITY PULLS OBJECTS DOWN AT AN ACCELERATION OF 9.8 m/s 2

Example  Scooby-Doo has a mass of 15 kg. What is his weight on earth?

Practice Questions  Complete the practice questions on the back of your c-notes

Exit Ticket  Complete your exit ticket silently