Momentum

• What is momentum?

  A property of all moving objects
• How is momentum calculated?

  Mass multiplied by velocity
• What is the momentum of a 4500 kg dinosaur moving at 12 m/s?

  54000 kg m/s
• What is the momentum of a 1200 kg car traveling at 25 m/s?

  30000 kg m/s
• What type of quantity is momentum?

  A vector quantity
• If the dinosaur has positive momentum, what is the car's momentum if it moves in the opposite direction?

  Negative momentum
• What does the conservation of momentum principle state?

  Total momentum before equals total after
• How do you find the total momentum before a collision?

  Add the momentums of both objects
• What is the total momentum of a dinosaur with 54000 kg m/s and a car with -30000 kg m/s?

  24000 kg m/s
• What does a positive total momentum indicate about direction?

  Movement to the right
• How do you calculate the shared velocity after a collision?

  Velocity equals momentum divided by mass
• What is the combined mass of a 4500 kg dinosaur and a 1200 kg car?

  5700 kg
• What is the velocity of the combined particles after the collision?

  1. 4 m/s to the right
• What happens to momentum when stationary objects collide?

  Total momentum remains zero
• What is the initial momentum of a stationary gun?

  Zero momentum
• What happens to the gun's momentum when it fires a bullet?

  Gun recoils with equal momentum
• How do you calculate the bullet's momentum if it has a mass of 5 grams and a velocity of 120 m/s?

  0.6 kg m/s
• What is the equation for the gun's momentum if its mass is 2 kg and velocity is unknown?


  2v
• How do you set up the equation for the gun and bullet's momentum?

  2v + 0.6 = 0
• What is the recoil velocity of the gun if its momentum equals negative 0.6?

  • 0.3 m/s
• What does a negative recoil velocity indicate?

  Movement in the opposite direction
• What is the symbol for momentum?

  p
• How can the momentum equation be expressed using its symbol?

  p = mv
• What are the key concepts of momentum discussed in the video?

  • Momentum is mass times velocity
  • Momentum is a vector quantity
  • Conservation of momentum principle
  • Total momentum before equals total after
  • Momentum can be zero for stationary objects
• What are the steps to calculate the recoil velocity of a gun after firing?

  1. Calculate bullet's momentum
  2. Set up momentum equation: gun's momentum + bullet's momentum = 0
  3. Solve for gun's velocity
• What is momentum equal to?

  Mass times velocity
• How does applying a force affect an object's momentum?

  It changes the object's momentum
• If a 2 kg particle travels at 5 m/s, what is its momentum?

  10 kg m/s
• What happens to momentum when velocity increases?

  Momentum also increases
• What is the new momentum of a 2 kg particle traveling at 8 m/s?

  16 kg m/s
• What is the equation for calculating force based on momentum change?

  Force = change in momentum / time
• If the change in momentum is 6 kg m/s over 0.5 seconds, what is the force applied?

  12 N
• What is the initial momentum of an object at rest?

  Zero
• How do you calculate the force required to accelerate a 600 g ball to 14 m/s in 0.1 seconds?

  Use the momentum change equation
• What is the mass of a 600 g ball in kilograms?

  0.6 kg
• What is the final momentum of a 600 g ball accelerated to 14 m/s?

  1. 4 kg m/s
• Why is spreading the change in momentum important during car crashes?

  It reduces the force experienced
• What safety features help reduce injury during car crashes?

  • Crumple zones
  • Seat belts
  • Airbags
  • Helmets
  • Crash mats
• How do crumple zones function in a car?

  They absorb impact and extend stopping time
• What are the two functions of seat belts?

  Prevent ejection and slow down occupants