Momentum, Newton's Laws and Circular Motion Flashcards
Define linear momentum.
Mass x velocity
What is the principle of the conservation of momentum?
The total momentum in any specified direction remains constant.
What is a closed system?
A system in which no external forces act
What are the two types of collision?
Perfectly elastic and inelastic
What is a perfectly elastic collision?
A collision in which kinetic energy is conserved
What is an inelastic collision?
A collision in which kinetic energy is not conserved
What two things are always conserved in a collision?
Momentum and total energy
What is Newton’s First Law?
An object will remain at rest or keep travelling at a constant velocity unless it is acted on by an external force
What is Newton’s Second Law?
The net force acting on an object is equal to the rate of change of the object’s linear momentum (as the Newton is defined to make the constant of proportionality one). The net force and the change in momentum are in the same direction.
What is the special case of Newton’s Second Law?
For an object of constant mass, F=ma
What is Newton’s Third Law?
When two bodies interact, the forces they exert on each other are equal and opposite, and of the same type (eg magnetic, gravitational…)
What is the impulse of a force?
- The product of the force and the time it acts for (Ft)
- The change in momentum (mv-mu)
- The area under a force against time graph
What is angular displacement?
The angle through which an object travelling in circular motion has moved
Define the radian.
One radian is the angle subtended at the centre of a circle by an arc of length equal to the radius of a circle
How do you convert from degrees to radians?
Multiply by pi/180