Question #593cb

2 Answers
Oct 12, 2015

Force #(vecF)#is a push or a pull and is measured in Newtons (N)

Impulse #(vec I)#gives a measure of how long the force acts on the objects and is equal to the change in momentum brought about.
Its units is hence either #N.s or kg.m//s#

From Newton's 2nd Law of Motion, the resultant force acting on an objects is equal tot he rate of change of momentum brought about, ie
#sum vecF=(dvecp)/(dt)=d/dt(mvecv)#
Hence #vecFdt = vecI = m d vecv#

Oct 12, 2015

The impulse gives you the average over time of a rapidly varying force.

Explanation:

Consider a force #F(t)# not constant but function of time such as the one experienced by an object (tennis ball) during an impact:
The force varies rapidly between two instants #t_1# and #t_2# so that:
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where #F_m# is the mean value of the force so that the grey square area is equal to the red total area under the original curve.