Momentum

• What is momentum defined as?

  Momentum is defined as the product of mass and velocity.
• Why does a cheetah have more momentum than a boy walking?


  A cheetah has more momentum because it has greater mass and velocity.
• What is the formula for calculating momentum?

  Momentum = Mass x Velocity
• What does it mean that momentum is a vector quantity?


  It means momentum has both size and direction.
• If a cheetah has a mass of 50 kg and is running at 60 m/s, what is its momentum?


  $p =$$m \times v =$$50 \times 60 =$$3000 \text{ kg m/s}$
• If a boy has a momentum of 75 kg m/s and a mass of 30 kg, what is his velocity?


  $v =$$\frac{p}{m} =$$\frac{75}{30} =$$2.5 \text{ m/s}$
• What does the conservation of momentum state?


  It states that total momentum before an event is the same as total momentum after the event in a closed system.
• How do you calculate the total momentum before and after a collision?


  • Total momentum before = Total momentum after
  • Use the formula: \( p = m \times v \)
• In a collision, if a 1500 kg car is traveling at 25 m/s, what is its momentum before the collision?


  $p =$$m \times v =$$1500 \times 25 =$$37500 \text{ kg m/s}$
• If a 1500 kg car crashes into a 1000 kg parked car and they lock together, what is their combined mass?


  Combined mass = 2500 kg
• After the collision, if the total momentum is 37500 kg m/s and the combined mass is 2500 kg, what is the velocity of the two cars moving together?


  $v =$$\frac{p}{M} =$$\frac{37500}{2500} =$$15 \text{ m/s}$
• What are the key concepts of momentum in physics?

  • Momentum is mass times velocity.
  • It is a vector quantity.
  • Conservation of momentum applies in closed systems.