Motion in 1 and 2 dimensionsPhysics Year 12 2012

By PresenterMedia.com

Which laws govern

our universe?

Newton’s First Law

Newton’s Third Law

Newton’s Second Law

The Law of Gravity

Conservation of EnergyConservation of

Momentum

Newtonian

Mechanics

The Force be With You – huh?

5400N

1600kg400Kg

Sample 1.4 continuedThe resultant force forward creates the acceleration of the car and trailer

If there is a trailer attached, the trailer and car accelerate individually at the same rate as the whole system

The resultant force on the trailer is composed of the forceforward from the car and the friction opposing its motion

The force on the car from the tow rope is the same as the force on the trailer exerted by the rope

The Force be With You – huh?

The Force be With You – huh?

• We use formulae to help make calculations easier• We write what we know on a diagram• We write down what we want to know• We choose the easiest formula• We calculate the answer• We check that our answer makes sense• We check the units

• We describe motion using graphs

GRAPHS and FORMULAS

Draw Label

Calculate

v = u + atx = ut + ½ at2

v2 = u2 + 2ax

KE = ½ m v2

PE = mgh

IN ELASTIC COLLISIONS

• Kinetic Energy is conserved and is not considered to be “lost” as sound, heat, or light

• Kinetic Energy is not conserved but is transformed into heat, sound and /or light

IN INELASTIC COLLISIONS

Conservation of Energy and MomentumMomentum is conserved in all collisions BUT

Circular Motion

v

v

v

v

Is there anyacceleration?

Circular Motion

Velocity vector rotates by 2

So acceleration, a = 2/T

But V = 2where R is the radius of the circle

So a = ? Or ???

Circular MotionBilly Teahttp://www.youtube.com/watch?v=Hml7RVFULCA&feature=youtube_gdata_player

Minidromehttp://www.youtube.com/watch?v=kghtRevkUJA&feature=youtube_gdata_player

NASCARShttp://www.youtube.com/watch?v=yZa_S93bQWY&feature=youtube_gdata_player

Loop the Loop in a real carhttp://www.youtube.com/watch?v=wiZoVAZGgsw&feature=youtube_gdata_player

Bike and Cars circular trackhttp://www.youtube.com/watch?v=hZOekFFSoWI&feature=youtube_gdata_player

vectorshttp://www.youtube.com/watch?v=J0a6yoQ6ZRY&feature=youtube_gdata_player

Science theatrehttp://www.youtube.com/watch?v=L6-kn2tB-9E&feature=youtube_gdata_player

Projectile Motion

http://www.youtube.com/watch?v=rMVBc8cE5GU&feature=related

http://galileo.phys.virginia.edu/classes/109N/more_stuff/Applets/ProjectileMotion/enapplet.html