Question #59015

1 Answer
Jan 23, 2017

17600" pdl"

Explanation:

In FPS system of units
30" mph"=30xx5280/3600=44 " ft s"^-1
Using the kinematic equation connecting quantities of interest: initial velocity u, final velocity v, acceleration a and time t

v=u+at

Inserting given quantities
44=0+axx8
=>a=44/8=5.5" ft s"^-2

From Newton's Second Law of Motion we know that Force F=massxxa

Inserting given and calculated values we get

F=3200xx5.5=17600" pdl"