• 5th
• Chapter 5 Test
• 6th/7th
• Chapter 5 Test
• Car Collisions: It's basic physics
• Intro. to My Car's Safety

Tuesday, December 22

• 5th
• Car Collisions: It's Basic Physics
• Work on My Car's Safety
• 6th/7th
• Work on My Car's Safety

Wednesday, December 23

• 5th/6th
• Work on My Car's Safety
• 7th
• Work on My Car's Safety

Thursday, December 24 through Sunday, January 3 – No school – Winter Break

Monday, January 4

• 5th
• Defining momentum and impulse
• Some example problems
• 6th/7th
• Defining momentum and impulse
• Some example problems
• *More Chapter 6 Example Problems
• High speed video analysis

Tuesday, January 5

• 5th
• The Bounce effect
• * More Chapter 6 Example Problems
• Law of Conservation of Momentum
• Difference between elastic and inelastic collisions (coefficient of restitution)
• 6th/7th
• Law of Conservation of Momentum
• Difference between elastic and inelastic collisions (coefficient of restitution)
• The Bounce effect
• High speed videography examples
• * Collision example problems
  • A 1.2 kg snowball moving at 18 m/s strikes a 0.70 kg top hat on a snowman. They stick upon colliding. Calculate the final speed of the hat and snowball.
  • A 53 kg boy runs at a velocity of 6.5 m/s and jumps on a skateboard with a mass of 2.5 kg that is already moving at 3.0 m/s. What is the combined speed of the boy and skateboard?
  • An 8.1 kg rifle fires a bullet with a mass of 0.011 g at a velocity of 450 m/s. What speed does the rifle move backward? Compare the kinetic energies of the rifle and the bullet.
  • A tennis ball with a mass of 0.13 kg moves toward a player at a speed of 35 m/s. The player makes the 1.8 kg racquet move at 51 m/s toward the ball and the racquet slows to a speed of 45 m/s. What is the final speed of the ball?

Wednesday, January 6

• 5th/6th
• P. 181, 1-6 due
• Go over problems
• *Collision example problems
  • A 1.2 kg snowball moving at 18 m/s strikes a 0.70 kg top hat on a snowman. They stick upon colliding. Calculate the final speed of the hat and snowball.
  • A 53 kg boy runs at a velocity of 6.5 m/s and jumps on a skateboard with a mass of 2.5 kg that is already moving at 3.0 m/s. What is the combined speed of the boy and skateboard?
  • An 8.1 kg rifle fires a bullet with a mass of 0.011 g at a velocity of 450 m/s. What speed does the rifle move backward? Compare the kinetic energies of the rifle and the bullet.
  • A tennis ball with a mass of 0.13 kg moves toward a player at a speed of 35 m/s. The player makes the 1.8 kg racquet move at 51 m/s toward the ball and the racquet slows to a speed of 45 m/s. What is the final speed of the ball?
• 7th
• P. 181, 1-6 due
• Go over problems

Thursday, January 7

• 5th/6th
• P. 182, 8-13 due
• Go over problems
• *Intro. to ballistic pendulum lab
• Train crashes
• 7th
• P. 182, 8-13 due
• Go over problems

Friday, January 8

• 5th
• My Car's Safety due
• Ballistic pendulum lab
• 7th
• My Car's Safety due
• Intro. to Ballistic pendulum lab
• Train crashes

Monday, January 11

• 5th
• P. 182, 18-22 due
• go over problems
• 6th/7th
• P. 182, 18-22 due
• go over problems
• *Ballistic pendulum lab

Tuesday, January 12

• 5th
• Energy conservation in collisions
• Two dimensional collisions
  • A 1250 kg car moving at 20.5 m/s collides with a 1700 kg car in an inelastic collision. Determine the speed at which the two cars move together after the collision. Determine the change in kinetic energy. Determine the average force exerted on the first car if the crumple zone is 1.3 m long.
  • A space ship with a mass of 7600 kg is moving at 125 m/s. Mission control decides to change the direction of the rocket by 30° by expelling a propellant at 3200 m/s perpendicular to the space ship. What mass of propellant must be expelled?
  • A compact car with a mass of 1875 kg is moving north at 25.5 m/s. It collides inelastically with a truck with a mass of 2250 kg moving west at 30.5 m/s. Determine the final velocity of the vehicles as they move off together. If the coefficient of friction is 0.80 how far do they slide?
• *Ballistic pendulum lab makeups
• Work on homework problems
• 6th/7th
• A space ship with a mass of 7600 kg is moving at 125 m/s. Mission control decides to change the direction of the rocket by 30° by expelling a propellant at 3200 m/s perpendicular to the space ship. What mass of propellant must be expelled?
• * More examples
  • Your friend was in a car accident and wants your help. She was driving her 1265 kg car north on Oak Street when she was hit by a 925 kg compact car going west on Maple Street. The cars struck and slid 23.1 m 42° N of W. The speed limit is 50 mph (22 m/s) and the coefficient of friction is 0.65. Who was at fault? (There are no witnesses who can attest to who had a green light and the courts will find a speeder at fault.)
• Work on homework

Wednesday, January 13

• 5th/6th
• P. 183, 25-27, 29-30 due
• Questions?
• Collect problems
• Your friend was in a car crash and wants your help. She was driving her 1265 kg car north on Oak Street when she was hit by a 925 kg compact car going west on Maple Street. The cars struck and slid 23.1 m 42° N of W. The speed limit is 50 mph (22 m/s) and the coefficient of friction is 0.65. Who was at fault? (There are no witnesses who can attest to who had a green light and the courts will find a speeder at fault.)
• * My Car's Safety Results
• 7th
• P. 183, 25-27, 29-30 due
• Collect problems
• My Car's Safety Results

Thursday, January 14

• 5th/6th
• Ballistic Pendulum Lab due
• Go over yesterday's problems
• *
• 7th
• Ballistic Pendulum Lab due
• Go over yesterday's problems

Friday, January 15

• 5th
• More Car Safety trends
• Work on homework
• 7th
• Work on homework

Monday, January 18 – No School – Martin Luther King, Jr. Day

Tuesday, January 19

• 5th
• P. 183, 41-44 due
• Go over problems
• 6th/7th
• P. 183, 41-44 due
• Go over problems
• * Intro. to chapter 7
• Circular motion: defining centripetal acceleration and centripetal force
• Why centrifugal forces are fictional forces

Wednesday, January 20

• 5th/6th
• Chapter 6 Review due
• Go over problems
• * Intro. to chapter 7
• Circular motion: defining centripetal acceleration and centripetal force
• Why centrifugal forces are fictional forces
• 7th
• Chapter 6 Review due
• Go over problems

Thursday, January 21

• 5th/6th
• Circular motion examples
• * More examples
• 7th
• Circular motion examples

Friday, January 22

• 5th
• Chapter 6 Test
• 7th
• Chapter 6 Test