Physics paper 2 - AQA Triple Higher

• Finding resultant force at right angles

  Use Pythagoras theorem
• If forces are balanced (add up to zero), the object will not accelerate, following Newton's first law of motion
• Work done equals force times distance moved, representing energy transferred by a force
• Vector

  An arrow that shows the direction and magnitude of a force
• Hooke's Law states that Force equals spring constant times extension, applicable for elastic objects
• Weight is the force due to gravity acting on an object, calculated by multiplying mass by gravitational field strength (9.8 N/kg on Earth)
• Measure at eye level with the bottom of the spring against the ruler to avoid parallax error, a random error
• Energy stored in a spring is directly proportional to the force applied, leading to extension
• Forces can be contact forces (objects physically touching) or non-contact forces like magnetism, electrostatic forces, and gravity
• Displacement is a vector quantity with direction, while velocity is the vector form of speed
• Using trigonometry to find angles

  Use SOHCAHTOA, likely using tan
• Finding resultant force


  If two forces act on an object, the resultant force is found by adding the vectors. If going in opposite directions, one must be negative
• Ensure ruler zero mark is lined up with the bottom of the spring to measure extension accurately and avoid systematic errors
• Gravitational potential energy gained can be calculated as mass * gravitational field strength * height
• The unit for spring constant is newton per meter
• To lift an object at a constant speed, the lifting force must equal the weight of the object
• Pressure

  How concentrated forces are. Pressure is equal to force divided by area. The unit for pressure is Newton per square meter, also known as pascals (PA)
• Moment


  A turning force, for example, what you do with a spanner. It is equal to force times distance to the pivot
• The energy stored in the spring is equal to half k^ s
• Gas pressure is due to the collisions of gas particles with surfaces. It can be increased by adding more gas, reducing the volume, or raising the temperature to make particles move faster
• For any object falling, the acceleration is 9.8 m/s squared, the same as gravitational field strength
• Newton's equations of motion involve predicting an object's behavior with variables like displacement, initial velocity, final velocity, acceleration, and time. U is zero if it starts at rest, V is zero if it decelerates to a standstill, and for falling objects, a is the same as gravitational acceleration (9.8 m/s squared)
• If something is attached to the spring and then let go, the object would gain the same amount of kinetic energy in an ideal or closed system where no energy is lost to the surroundings due to heat
• Acceleration is the change in speed divided by time. The unit of acceleration is m/s squared. Negative acceleration indicates deceleration or slowing down
• A velocity-time graph can give you the distance traveled by calculating the area under the graph. Negative displacement is counted for areas under 0 m/s
• The deeper you go underwater, the greater the pressure due to the weight of the water above pushing down on you. Pressure can be calculated using the formula p = Hρg, where H is the height of the water column above you, ρ is the density, and g is the gravitational field strength
• Application of moments

  • Gears: a small gear can turn a large gear in order to increase the moment produced
• Newton's Third Law
• Newton's Second Law

  Unbalanced forces result in a resultant Force, which is equal to mass times acceleration (F=ma)
• Calculating total momentum in collisions


  Sum of individual momenta before the collision equals the total momentum after the collision. Total momentum is the sum of mass times velocity for each object involved
• Momentum


  Measure of how hard it is to get something to stop, equal to mass times velocity (p=mv). Momentum is conserved in collisions
• Kinetic energy isn't always conserved in collisions, but total momentum always is
• Overall stopping distance for a car consists of thinking distance and braking distance. Doubling speed doubles thinking distance and quadruples braking distance. Other factors affecting stopping distance include distractions, alcohol, drugs, brake condition, tires, road condition, and weather
• Newton's First Law

  When there's no resultant Force, an object's motion is constant, indicating no change in velocity. This could be due to no forces acting or balanced forces. Inertia is the term used to describe the tendency for an object's motion to stay constant unless acted on by a resultant Force
• Proving Newton's Second Law

  Use a trolley on a track being pulled by the weight of masses hanging over a pulley. Measure acceleration between two points using light Gates photo gates. Change the weight on the string, ensuring mass is transferred from hanger to trolley. Draw a graph of force against acceleration, showing a proportional relationship between F and a. The gradient gives the total mass of the trolley and slotted masses
• When rearranging to find the unknown in a momentum equation


  Pop your numbers in making sure that everything traveling to the left has a negative velocity, then rearrange to find the unknown
• In the case of the Cannon

  The cannon ball and the cannon have the same momentum but in opposite directions, adding up to zero, an example of recoil
• Waves

  All waves transfer energy without transferring matter, oscillations or vibrations are passed along instead of the particles themselves
• Examples of safety features in cars

  • Seat belts, airbags, crumble zones
• Ultrasound can be used to scan babies safely by timing how long it takes for the sound waves to return off different layers inside the body