2.3 Work and Energy Flashcards
Define Kinetic Energy
Objects that are moving have kinetic energy: when it moves faster it has more kinetic energy.
Define Work Done
Work done is the energy transferred to an object when it is moved
Define Gravitational Potential Energy
Objects that are above the ground have gravitational potential energy.
Define Hooke’s Law
The extension of a material is directly proportional to the force applied.
What’s the equation for Hooke’s Law?
Force = spring constant x extension of the spring.
What is the spring constant?
The gradient of a graph.
Define Elastic Potential
How the extension of a spring or other device has an energy potential
What is the equation for work done?
W= Fd (J=NM)
What’s the point of a seatbelt?
It prevents the person from being thrown forward in a crash and stretchy material absorbs some of the energy.
What is the equation for kinetic energy?
KE=1/2ms2 (J=1/2kg m/s2)
What’s the point of a crumple zone?
It makes the car slow down over a longer period of time so it decreases the deceleration. This means it decreases the force.
What is the equation for Gravitational Potential Energy?
PE=mgh (J=kg10M)
What is the equation for Elastic Potential?
W=1/2fx (J=1/2NM)
What’s the point of an airbag?
It acts as a cushion, making the passenger slow down over a longer period of time.
What is energy transfer?
Energy cannot be created or destroyed, and is instead transferred between objects. Energy can be wasted by heat or sound loss, and can also be wasted by air resistance or friction.
