momimp

momimp - F net dt = ∆ p where the impulse of a force...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Linear momentum and the impulse-momentum theorem Definition of linear momentum of a particle Consider a system of N particles, each with a position vector, r i . The i th particle has mass m i and velocity, v i . We define the linear momentum of the particle by p i m i v i . The linear momentum of the system of particles is then written P Σ i p i . Next, we contemplate how to change the value of p for a particle. Obviously, the mass can not change and therefore to change p we must do it by changing v , i.e we must accelerate the particle. Newton’s second law gives F net = m d v /dt = d [m v ]/dt = d p /dt. This becomes for a system of particles, F ext net = d P /dt, Where, F ext net is the sum of only the external forces acting on the particles of the system.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Rearranging gives the impulse-momentum theorem
Background image of page 2
Background image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: , ∫ F net dt = ∆ p , where the impulse of a force is defined, I ≡ ∫ F dt. this is the area under F vs t graph For example, F net ∆ t = F net ∆ t = ∆ p where the average force is used. A consequence of the impulse-momentum theorem is the law of conservation of momentum : If the net external force acting on a system is zero, then the momentum of the system is constant. An important application is to collisions. In the simplest case we consider the collision of two particles in one-dimension, of which there are two extreme regimes. • completely inelastic Only momentum of the two-body system is conserved. • Elastic Both momentum and kinetic energy of the two-body system is conserved. EXAMPLES [in class]...
View Full Document

{[ snackBarMessage ]}

Page1 / 3

momimp - F net dt = ∆ p where the impulse of a force...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online