Kinetics KPE160 Exam Questions And Answers
Energy Storage
- Gravity
- Inertia
- Elasticity
Energy Transfer
- force of gravity
- contact and reaction forces
Energy Dissipation
Friction (several forms)
Mass
How much a body will resist acceleration
- scalar
Energy
"the capacity to do work"
1st Law of Thermodynamics
- can have many forms, cannot be created or destroyed
Mechanical Forms of Energy
- Kinetic Energy
- Gravitational Potential Energy
- Elastic Potential
Kinetic Energy
- energy stored in a moving body
- the capacity to do work via contact and reaction
- the quicker you move, the more kinetic energy you have
, - proportional to the square of your speed Gravity Potential Energy
- energy conserved by lifting the mass of something over your head above the Earth
- the higher up something is, the more gravitational potential energy it has Gravity
Potential Energy (simplified)
- What goes up is able to come back down on its own, using the energy provided by its
height Elastic Potential Energy
Energy stored by the elasticity of a deformed body The ability to do work by a body
returning to its neutral shape e.g. a rubber band Work A scalar measure of energy
transfer from one body to another Force A way energy is transferred from one body to
another Measured in newtons Power The rate of doing work Mechanical Power The
product of force and velocity Two ways to be more powerful
- power = force x velocity
- be stronger [push harder]
- be faster [push faster]
Momentum
- linear momentum = inertia x velocity
- linear motion = mass (more mass = more linear resistance)
- "amount of motion"
- how hard it is to stop a moving object
- momentum is conserved by inertia in closed systems; constant
Gravity
- Force directed downwards (towards centre of Earth)
- proportional to mass
- stores energy and transfers energy
9.81m/s^2 = constant downward acceleration
everything falls at the same velocity unless affected by air resistance
Weight
the force of gravity
all objects fall equally fast toward Earth regardless of weight
Energy Storage
- Gravity
- Inertia
- Elasticity
Energy Transfer
- force of gravity
- contact and reaction forces
Energy Dissipation
Friction (several forms)
Mass
How much a body will resist acceleration
- scalar
Energy
"the capacity to do work"
1st Law of Thermodynamics
- can have many forms, cannot be created or destroyed
Mechanical Forms of Energy
- Kinetic Energy
- Gravitational Potential Energy
- Elastic Potential
Kinetic Energy
- energy stored in a moving body
- the capacity to do work via contact and reaction
- the quicker you move, the more kinetic energy you have
, - proportional to the square of your speed Gravity Potential Energy
- energy conserved by lifting the mass of something over your head above the Earth
- the higher up something is, the more gravitational potential energy it has Gravity
Potential Energy (simplified)
- What goes up is able to come back down on its own, using the energy provided by its
height Elastic Potential Energy
Energy stored by the elasticity of a deformed body The ability to do work by a body
returning to its neutral shape e.g. a rubber band Work A scalar measure of energy
transfer from one body to another Force A way energy is transferred from one body to
another Measured in newtons Power The rate of doing work Mechanical Power The
product of force and velocity Two ways to be more powerful
- power = force x velocity
- be stronger [push harder]
- be faster [push faster]
Momentum
- linear momentum = inertia x velocity
- linear motion = mass (more mass = more linear resistance)
- "amount of motion"
- how hard it is to stop a moving object
- momentum is conserved by inertia in closed systems; constant
Gravity
- Force directed downwards (towards centre of Earth)
- proportional to mass
- stores energy and transfers energy
9.81m/s^2 = constant downward acceleration
everything falls at the same velocity unless affected by air resistance
Weight
the force of gravity
all objects fall equally fast toward Earth regardless of weight
