Physics

• weight = mass X gravity
• Force


  A push or pull
• If an object is not moving the forces in it cancel out and are balanced. This is called equilibrium.
• Force is measured in newtons (N)
• forces can speed up or slow down objects
• The diagrams below show how different forces can affect the movement of a car.

  
• Acceleration - A change in velocity over time.
• Newton's first law states that if there is no net force acting on an object then its velocity will remain constant.
• Velocity - The rate at which something moves, measured as distance travelled per unit time.
• Distance - How far something has moved from its starting point.
• Mass - The amount of matter in an object.
• Momentum - The product of mass and velocity (p = mv).
• Weight - The gravitational pull between two masses.
• Speed - The magnitude (size) of the velocity vector.
• Momentum - Mass times velocity.
• Force - Any interaction between objects that causes them to accelerate.
• Force - A push or pull that causes acceleration.
• Friction - Resistance caused by contact between two surfaces moving against one another.
• Newton's First Law - An object at rest will remain at rest unless acted upon by an external force, and an object in motion will continue moving with constant speed and direction unless acted upon by an external force.
• Gravity - An attractive force between all matter, causing it to be pulled towards other matter.
• Mass - Measurement of how much matter is present in an object.
• If the force from the engine of the car is 500N and the force of air resistance is 300N, what will happen?

  The car will accelerate
• If the force from the engine of the car is 500N and the force of air resistance is 500N, what will happen?

  The car will reach a steady speed.
• If the force from the engine of the car is 500N and the force of air resistance is 700N, what will happen?

  The car will slow down
• A book is pulled down with a force of 5N and the table pushes up with a force of 5N, what will happen?

  The book will not move
• Drag is the resistance to motion. We call this friction. Friction is created 2 objects rub together.
• All metals are ductile
• independent variable

  what i change
• Dependent variable

  What i measure
• Hooke’s law

  the force applied to a spring is directly proportional to its extension until the breaking point of the spring.
• Weight = mass X gravity
• pressure is the force per area (force/area)
• What determines high pressure?

  1. Less area
  2. High force
• Pressure = force per unit area (N/m^2)
• Upthrust

  The force that keeps an object floating.
• Weight

  Weight is the force of on a object
• For an object to float, the upthrust is equal to the weight.
• When the upthrust is lower than the weight, the object will sink
• When the upthrust is higher than the weight of the object, it will float
• Density = mass / volume