FM1 Chapters 1-5 Flashcards
Equation for momentum
p=mv
Equation for impulse
I= change in momentum= mΔv
I=mv - mu
What is the principle of conservation of linear momentum?
Total momentum before and after an impact are equal
Equation for work done
Component of force in direction of motion x distance moved in direction of force
Equation for gravitational potential energy
E = mgΔh
Equation for kinetic energy
Ek = 0.5mv^2
How is work done to accelerate a particle horizontally related to kinetic energy?
Work done = change in Ek
What is the principle of conservation of mechanical energy?
When no external forces other than gravity do work on a particle during its motion, the sum of the particle’s Ek and Ep remains constant
What is the work-energy principle?
The change in the total energy of a particle is equal to the work done on the particle
Equations for power
P = E/t
P = Fv, F is the driving force produced by engine and v is the speed of vehicle
What are two equations for Hooke’s law?
T=kx
T= λx/l
λ: modulus of elasticity
x: extension
l: natural length
Equation for elastic potential energy
Ee= 0.5ke^2
Ee = λx^2/2l
Equation for coefficient of restitution
e= speed of separation/ speed of approach
How do components of velocity change when a ball collides with a wall?
Component of velocity parallel to surface is unchanged
Component of velocity perpendicular to wall is multiplied by e
Where does the impulse act for a sphere colliding with a wall?
Impulse on the sphere acts perpendicular to the surface, through the centre of the sphere
What is the equation involving e, v, u and I for an oblique collision between a sphere and wall?
e = -v.I / u.I
Where does the impulse act for a collision between two spheres?
Reaction force between two spheres acts along line of centres so impulse also acts along line of centres
How do the components of velocities change during a collision between two spheres?
Component perpendicular to line of centres is unchanged
Newton’s law of restitution applies to components of velocities of spheres parallel to line of centres
Conservation of momentum applies parallel to line of centres
