Further Mechanics 1 Flashcards
Equation for momentum
Mass x velocity
What must you remember when calculating momentum?
Remember signs - one direction is positive and one negative
What are the two possible units for momentum?
Ns or Kgm^-1
Is momentum a vector or scalar?
Vector
Is impulse a vector or scalar?
Vector
What is impulse?
The change in momentum
When a constant force acts on an object for a certain time, what is the equation for impulse?
Force x time
What is the equation for impulse using momentum?
Final momentum - initial momentum (mv - mu)
What are the units of impulse?
Ns
What does Newton’s third law state?
When two bodies collide, they ever equal and opposite forces on each other
What is the principle of the conservation of momentum?
The changes in momentum (impulse) are equal but in opposite directions, so they cancel out
What does coalesce mean?
Two particles stick together
Equation for the conservation of momentum
m1u1 + m2u2 = m1v1 + m2v2
When a question asks for a vector, what must you state?
Direction and magnitude
When modelling with particles, what is important to remember about collisions?
Collisions are direct and there is no spinning
When modelling collisions across a smooth surface, what is important to remember?
There is no friction and motion is in a straight line
How should you treat particles connected by a light inextensible string?
As a coalesced particle
What is the impulse-momentum principle?
The impulse of a force is equal to the change in momentum
What is the principle of the conservation of momentum?
The total momentum before impact equals the total momentum after impact
How to find the magnitude of a vector
Use trig
How to find the angle of impulse
Use Pythagoras
