Acyclist has a momentum of 771.9 kg m/s. if her mass is 93 kg what is the speed of the cyclist?
a. 8.3 m/s
b. 12.1 m/s
c. 13.2 m/s
d. 4.4 m/s

Consider a 1000 w iron whose base plate is made of 0.5 cm thick aluminum alloy 2024-t6 (ρ = 2770 kg/m3 and cp = 875 j/kg°c). the base plate has a surface area of 0.03 m2. initially, the iron is in thermal equilibrium with the ambient air at 22°c. assuming 90% of the heat generated in the resistance wires is transferred to the plate, determine the minimum time needed for the plate temperature to reach 200°c.