Mechanics - Work Energy and Power Flashcards
What symbol can be used for work done?
What is the short version of the 1st word done equation?
What is the long version of the 1st word done equation?
Work done = component of force in the direction of motion X distance moved in direction of the force
What is the equation for work done against gravity?
What is work done against gravity equal to?
Potential energy/gravitational potential energy
What is the reason for the long version of the first work done equation?
A question may say that a force is inclined at 25 degrees, so you need to find the horizontal force to use in the equation
What is the equation for kinetic energy?
What is the equation for potential energy?
What 2 things need to be remembered when using the equation for potential energy?
h is vertical height
Potential energy needs to be decided from a fixed point
What is the 2nd equation for work done?
What do you need to do for calculations if velocity is given as a vector?
Work out the magnitude of v and use that
What do you know about kinetic energy that is pretty useless?
It can’t be negative
What is the long version of the conservation of momentum?
Conservation of momentum definition:
When no external force (other than gravity) does work on a particle during its motion, the sum of the particles kinetic energy and potential energy remains constant
What is the short version of the conservation of momentum?
What else do you know work done is equal to?
The change in total energy
What is the equation for power?
