Week 5 Work, CoM, reduced mass

Question 1

define work done

Answer 1

the product of force and the distance travelled in the direction of the force

Question 2

what is the work-energy theorem

Answer 2

the work done by the resultant force on a particle is equal to the change in KE of the particle

Question 3

define power

Answer 3

rate of change of work

Question 4

define the centre of mass of body

Answer 4

part of the body that moves as though all the mass were concentrated at that point and all external forces applied there

Question 5

what is the position of CoM equation

Answer 5

xcm = m1x1 + m2x2 .. mnxn / M

Question 6

what is the KE and CoM relationship

Answer 6

The KE of a system of particles equals the KE associated with the motion of the CoM

Question 7

what is the total KE of a system equation

Answer 7

KEtot = KEcom + Krel

Question 8

define is reduced mass

Answer 8

quantity that describes the relative motion of two particles

Question 9

what is the vcom equation

Answer 9

vcom = m1v1 + m2v2 … + mnvn / M

Question 10

what is the vrel equation

Answer 10

vrel = v1 - v2

Question 11

what is the reduced mass equation

Answer 11

μ = m1m2 / m1 + m2