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Calculate the total anticlockwise *moments Calculate the total clockwise moments Is this system in equilibrium?*moment = another name for torque4 kg2 kg20 cm35 cm20 cm2 kgStarterA car is moving at a steady velocity of 20 ms-1. The mass of the car and its passengers is 1200 kg.If the thrust force is 4000 N, find the friction force.Draw a free body diagram with labels AND sizes of all forcesWhat would happen to the cars motion if the thrust force was suddenly removed?1PeterJacob TFrankie2LiamDavidScott3Will RTimJakob O4Will KCallumBest5HaydenSamRodrigo6TomWill S(Cameron)

Free Body DiagramsFinish by Tomorrow (Friday)Homework Booklet Sheet #5 Q 1 ~ 9 (except for Q5)Purple Worksheets pg. 52 ~ 54Extension work (optional): Activity 9A textbook pg. 109Tutorials 2 hours (expected)

Franky Friday after schoolWill K Friday after schoolJakob Friday after schoolJacob Friday after schoolWill S Friday after schoolTim Friday after schoolDavid Friday lunch time (50 min)Sam Sunday 10amScott Sunday 10amWhat is Torque?Turning effect about a pivotForce that tries to rotate an objectSpinning force

= torque (a.k.a. moment)F = forced = distance from the pivotTorque is measured in ______Clockwise or Anticlockwise

PivotPivot = the stationary point about which the torque can act or an object can revolve

The relationship between F and d

Question A force of 10 N which acts at 8 cm from the pivot is needed to lift the cap off a bottle of soft drink as shown below.Find the size and the direction of the torque being applied.

What is Equilibrium?Fnet = 0net = 0net = 0 Total Total Clockwise + Anticlockwise = Moments Moments0It means Calculate the anticlockwise torque Calculate the clockwise torqueWhich is greater? Anticlockwise torque or clockwise torque?12 kg8 kg60 cm40 cmExample #1 Calculate the anticlockwise torque Calculate the clockwise torqueWhich is greater? Anticlockwise torque or clockwise torque? 7 kg13 kg35 cm65 cmExample #2 Calculate the total anticlockwise *moments Calculate the total clockwise moments Is this system in equilibrium?*moment = another name for torque9 kg4 kg30 cm40 cm30 cm4 kgExample #3

Aaron (70 kg)Bob (50 kg)Aaron is 1.5 m away from the pivot whereas Bob is 2 m away from the pivot. What will happen to the see saw?Where do you think Bob will have to be to balance the see saw?

The mass of the rock is 100 kg and it is sitting on one end of the stick, 50 cm away from the pivot as shown in the diagram.If the man exerts a force of 200 N downwards to the other end of the stick which is 3 m away from the pivot, would he be able to lift the rock?

"Give me a place to stand and I will move the earth!"ArchimedesIs this system at equilibrium?700 g300 g70 cm30 cmCentre of MassThe weight of an object acts down through the objects centre of mass.This is the point at which, if an object is suspended or pivoted, the object will balance.Watch out for any objects of negligible mass700 g300 g70 cm30 cm700 g300 gFw (weight of the ruler)Fs (support force)7 N3 NFnet = 07 + 3 + Fw + Fs = 0Torque ExercisesActivity 9B (pg. 116) Q5, 6, 7 onlyHomework Booklet Worksheet #12 first page onlyExtension Work: Homework Booklet Worksheet #12 second page AND Activity 9B Q8, 9, 10, 11 and 12