An archer shoots an arrow into a target using a bow. If the "action" force is the force of the bowstring against the arrow, what is the "reaction force? a. the arrow's push against the bowstring
b. weight of the arrow
c. the archer's hand gripping the bowstring
d. the bowstring's force on the bow

Given the position vector of the particle r(t)=(t+1)i+(t^2−1)j+2t k, find the particle's velocity and acceleration vectors at t=1

Abike rider starts from rest and accelerates 28.0 meters down a slope in 5.00 seconds. what is her acceleration? select one: a. 3.21 m/sec2 b. 1.75 m/sec2 c. 9.80 m/sec2 d. 2.24 m/sec2

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.