Density and Pressure Flashcards
Density symbol
rho (ρ)
Density formula
Density = mass/volume
ρ = mass/volume
Pressure formula
Pressure = Force perpendicular to the area/Area
p =F/A
% difference formula
% Difference = accepted value −calculated value/accepted value × 100
Pressure at depth of fluid
p = hρg
What there must be for an of an object floating?
For equilibrium, force upward = weight downward
How to calculate the upthrust of an object
Upthrust = Weight of object or U = mg
How to calculate the forces acting on an object from all sides
Ftop = Ahρg and
Fbottom = A(h + x)ρg
Fres = U = A(h + x)ρg- Ahρg = Axρg
Archimedes’ principle
The weight of the fluid displaced by the object is equal to the upthrust of the liquid on the object.
What happens when work is done
Work is done when a force moves its point of
application.
Work done equation
work = force x distance moved in the direction of the force
Is work scalar or vector
A scalar quantity
If the direction of the force and the distance moved are
not in the same direction how do you find W?
W = F x cos θ
How to find work done on force distance graphs?
The area under the curve is equal to the work done.
Why is energy needed?
Energy is needed to move objects, to change their
shape or to warm them up.
