A wheel with an 8 cm radius has a 0.5 cm axle. A string is wrapped tight around the axle. If the string is attached from the 0.5 cm axle to a syringe plunger that pulls it 10 cm, how far will the wheel and axle move? a
80 cm
b
0.5 cm
c
160 cm
d
100 cm

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.

Air enters a horizontal, constant-diameter heating duct operating at steady state at 290 k, 1 bar, with a volumetric flow rate of 0.25 m°/s, and exits at 325 k, 0.95 bar. the flow area is 0.04 m2. assuming the ideal gas model with k = 1.4 for the air, determine (a) the velocity at the inlet and exit, each in m/s, and (c) the rate of heat transfer, in kw flow rate, in kg/s, (b) the mass kg 0.3

Determine (a) the maximum thermal efficiency of reversible power cycles operating between a hot reservoir at 1000°c and a cold reservoir at 200°c and (b) the maximum cops for reversible refrigeration and heat pump cycies, respectively, between 28°c and 14°c.