Unit 1

• Density definition and equation

  mass per unit volume
• speed equation

  distance/time
• deceleration definition

  decrease in velocity per unit time
• mass definition

  property that resists change in motion and direction
• vectors definition

  quantities that have both a magnitude and a direction
• scalars definition

  quantities that have only a magnitude
• Force definition and equation

  change in momentum per unit time. F= ΔP/t
• Definition of normal contact force

  reaction force of the ground on the object. It's always perpendicular to the ground.
• Definition of frictional force

  Resisting force between two surfaces that are moving against each other
• Definition of upthrust force

  Vertically upward force that acts on a body when its fully or partially submerged in a fluid
• What factors affect upthrust force?

  Density of the fluid and volume of the object
• What increases the frictional force?

  Roughness of the surface or weight
• What is air/water resistance?

  Force resisting the motion of a body through fluids
• What affects air/wate resistance?

  Speed or the surface area
• What is tension force?

  Force in pulling ropes, strings, or springs
• What is centripetal force?

  Force acting on an object when its moving in a circular motion or a curve. It's always directed towards the center.
• What factors affect centripetal force

  Mass, radius, speed.
• What is deformation

  change in shape or length of something due to applied force
• What is Hooke's Law?

  Force and extension are directly proportional
• What is the spring constant?


  Property of the spring that defines its stiffness
• Spring constant equation


  K= F/X
• What is moment?


  Measure of the turning effect of a force around a pivot
• Moment equation

  Force x perpendicular distance from pivot
• What is equilibrium


  When the resultant force and moment is zero
• What is center of mass?

  Point where the whole body weight is considered to act
• Momentum equation

  mass x velocity
• Impulse (change in momentum) equation

  Force x time

  mv - mu = m(v-u)
• Law of conservation of momentum

  Total momentum is always the same for an isolated system
• What is gravitational potential energy

  Energy gained due to the position of theb object in gravitational field
• GPE equation

  mass x g x height
• What is electrical energy

  Energy due to the flow of charges through a conductor
• What is heat energy


  It is gained due to contact between two forces.

  Heat energy flows from one body to another due to differences in the temperature
• What is kinetic energy

  Energy due to the speed of the object
• K.E equation


  1/2mv^2
• What is internal energy


  Sum of kinetic and potetional energy of molecules
• Law of conservation of energy

  Energy cannot be created or destroyed; it may be transformed from one form into another.
• What is a renewable source of energy

  Sources that won't vanish
• Examples of renewable energy

  biomass, geothermal, solar, wind, water sources
• Non-renewable energy examples

  Fossil fuels and nuclear fuels
• Work done equation

  force x parallel distance