4. Forces Flashcards
What is Hooke’s Law?
Hooke’s Law states that, provided the proportionality limit is not exceeded, the extension/compression of the body is proportional to the applied load.
What is F external?
F external is the force exerted by the an external agent on the spring, distorting it from equilibrium position.
F external = kx
What is F internal
F internal is the force exerted by the spring to restore itself to equilibrium position.
F internal = -kx
What is the formula for spring constant k?
k=F/x
What is the formula for elastic potential energy?
U = 1/2 kx²
What is pressure?
pressure is the amount of force per unit area
What is the formula for pressure in liquid?
P = F/A = m(fluid)g /A = (V (fluid) 𝛒g) / A = (hA𝛒g) / A
= h𝛒g
What is upthrust ?
upthrust originates from the difference in pressure between the top and bottom surfaces of the immersed body
What is the formula of upthrust?
Upthrust = Vf 𝛒f g
V is the volume displaced
What is Archimedes principle
Archimedes principle states that for a submerged or floating object in a fluid, it experiences upthrust equal in magnitude and opposite in direction to the weight of fluid displaced.
What is the Principle of Floatation
The Principle of Floatation states that for an object floating in equilibrium, the upthrust is equal in magnitude and opposite in direction to the weight of the object.
What is centre of gravity?
The centre of gravity of an object is the point at which the whole weight of the body seems to act on.
What is moment of a force?
Moment of a force is the turning effect of a force. It is equal to the product of the force and the perpendicular distance of the line of action of the force from the pivot
m = F x d
What is a couple?
A couple consists of two equal and opposite parallel forces whose line of action do not coincide.
What is torque?
Torque of a couple is the turning effect of a couple. It is equal to the product of the force and the perpendicular distance between the two forces.
