Memory Anchor:

• Super Challenge:

  Stretch:

  Challenge:

Key Questions:

1. What is Newton's second law?
   • Newton's Second Law states the acceleration of an object is proportional to the resultant Force acting on the object, and inversely proportional to the mass of the object.
2. What is the typical mass of a cyslist, car and lorry?
   • the mass of a small family car is 2000Kg, cyclist is 100Kg and a lorry 50000Kg. These could be used along with information about speed or acceleration.
3. what is the momentum equation and units?
   • Momentum is defined by the equation: momentum = mass ? velocity p=mv, momentum, p, in kilograms metre per second, kg m/s, mass, m, in kilograms, kg, velocity, v, in metres per second, m/s
4. two model cars collide reversing into one another), the blue car has a of mass 1.2Kg and the red car has a mass of 1.4 kg they collide at speeds of 0.5m/s (blue) and 0.2m/s (red) what is the velocity of the cars after the collision?
   • 0.12m/s/s
5. The equations F = m × a and a = ( v - u ) / t combine to give what equation?
   • F = m Δ v / Δ t
6. (HT only) What is the definition of inertial mass?
   • (HT only) inertial mass is defined as the ratio of Force over acceleration.
7. What is conservation of momentum?
   • Conservation of momentum is when in a closed system, the total momentum before an event is equal to the total momentum after the event.
8. In terms of rate of change of momentum, how do different examples of safety features work?
   • air bags, seat belts, gymnasium crash mats, cycle helmets and cushioned surfaces. They deform and they increase the amount of time the person takes to come to a stop. They provide a softer surface (like a pillow) and seatbelts protect people in two ways during a crash. The seatbelt prevents the person being thrown about in the car, possibly through the windscreen or hitting themselves on the steering wheel or other objects. The seatbelt also stretches a little, while restraining the person during a crash. The stretching increases the amount of time it takes the person to stop. to prevent the people hitting themselves on hard objects
9. What is the symbol that indicates an approximate value or approximate answer?
   • ~ is the symbol that indicates an approximate value
10. Explain what happens to momentum in a collision?
    • The total momentum before the collision is the sum of both momentums.
11. What is inertial mass a measure of?
    • inertial mass is a measure of how difficult it is to change the velocity of an object
12. (HT only) What is the definition of inertia?
    • (HT only) The tendency of objects to continue in their state of rest or of uniform motion.