Impulse

• What is impulse in physics?

  Change in an object's motion due to force
• How is force defined in relation to momentum?

  As the rate of change of momentum

  
• How is change in momentum calculated?

  Final momentum minus initial momentum
• What type of quantities are force and momentum?

  Vector quantities
• What happens to the force if it opposes the initial velocity?

  The force is considered negative
• According to Newton's Third Law, what happens when a car hits a wall?

  The wall exerts an equal and opposite force

  
• If a car exerts a force of 300 N on a wall, what force does the wall exert on the car?

  -300 N

  
• What is the mass of a car that hits a wall at an initial velocity of 15 m/s?

  1500 kg
• If a car rebounds at 5 m/s after hitting a wall, what is its final velocity?

  5 m/s
• How long is the car in contact with the wall during the collision?

  3.0 seconds
• What is impulse when an external resultant force acts on an object?

  Change in the object's motion
• What is the formula for impulse?

  Impulse = F∆t
• In what units is impulse measured?

  Newton seconds (N s)
• What does Newton's second law state in terms of momentum?

  Resultant force equals rate of change of momentum
• How can impulse be measured indirectly?

  By calculating change in momentum
• What is the equation for change in momentum?

  Impulse = ∆p = mv − mu
• What does the variable 'm' represent in the impulse equation?

  Mass of the object
• What does 'v' represent in the impulse equation?

  Final velocity
• What does 'u' represent in the impulse equation?

  Initial velocity
• When can the impulse equations be used?

  When the force is constant
• How does impulse relate to force and time?

  A small force over long time equals large force
• How do rain and hail differ in terms of impulse?

  Hail has greater impulse than rain
• Why is more force required to hold an umbrella in hail?

  Hailstones have greater change in momentum
• How does increasing time affect force experienced by a person?

  It reduces the force experienced
• What happens when a fielder catches a high-speed cricket ball?

  It exerts a large force on their hands
• How does moving hands back while catching a ball help?

  Increases time for change in momentum
• What is the final velocity of the tennis ball after being struck?

  -20 m/s
• How do you calculate the impulse of the racket on the ball?

  Using the impulse equation with known values
• What does a negative impulse indicate about direction?

  It is opposite to initial motion
• What common mistake do students make regarding vectors?

  Not changing sign for direction changes
• What is the relationship between impulse and momentum?

  Impulse equals change in momentum