Work And Power Flashcards
What is the equation for work done?
Work done = force x distance moved in direction of force
What are units for work done?
Joules, J
What are the units for force?
Newtons, N
What are the units used for distance moved in direction of force?
Meters, m
What is power?
Power is the rare of energy transferred
What is the equation for speed?
Speed = distance/ time
What is the equation for power?
Power = work done/time taken
What is power measured in?
Watts, w
What is time taken measured in?
Seconds, s
1 watt = ? j/s
1 watt = 1 J/s
What could work done also be seen as?
Energy
What is equilibrium?
Where the forces on opposite sides are balanced and the objects are either balanced or moving at a constant speed
What are contact forces?
Objects affecting each other by touching
What are the three contact forces?
Push, pull, friction
What are non contact forces?
Forces affecting each other without touching
What are the three non contact forces?
Gravity, magnetic fields, electrostatic forces
Where do gravitational fields effect?
Around anything with mass
Where do electrostatic fields effect?
Around any charged object
Where do magnetic fields effect?
Around any magnet
What are the four rules of force pairs?
They do not cancel each other out
They act in different objects
They are the same size
They act in opposite directions
What is Newton’s third law?
For every force there’s an equal opposite reaction force
What are force pairs an example of?
Newton’s third law pairs
What type of force would a chair pushing up on you be?
Normal contact force
What are the three rules for forces on a single object?
May be the same type or different types
May cancel each other out (balanced
May not cancel each other out (unbalanced
What is weight?
The earth pulling (object) down. Caused by gravity
How can we draw a diagram to show vector forces?
Using arrows pointing in the correct direction in a scale diagram
What is a scalar quantity?
A scalar quantity has only a size (magnitude) and doesn’t have a direction
What’s an example of a scalar quantity?
Distance
What is a vector quantity?
A vector quantity has a size (magnitude) and a direction
What is an example of a vector quantity?
Displacement
Is charge a vector or scalar quantity?
Scalar
Is distance a vector or scalar quantity?
Scalar
Is energy a vector or scalar quantity?
Scalar
Is frequency a vector or scalar quantity?
Scalar
Is mass a vector or scalar quantity?
Scalar
Is pressure a vector or scalar quantity?
Scalar
Is speed a vector or scalar quantity?
Scalar