# ENGR 300 ENGR300 Homework 2 Solution

ENGR 300 ENGR/300 ENGR300 Homework 2

P2.8 – Give three examples of engineered products that have to be precisely a certain weight, and provide the weight.

P2.10 – Give three examples of engineered products designed to work well over a million times.

P2.25 – A team of design students working on a mousetrap-powered vehicle decides to use computer compact discs as wheels. The discs are lightweight and readily available. However, they must also be aligned and securely attached to the axles. Develop five design concepts for attaching wheels to a 5-mm-diameter axle. Compact discs are 1.25 mm thick, and they have an inner and outer diameters of 15 mm and 120 mm.

P3.2 – Express your height in the units of inches, feet, and meters.

P3.4 – A world-class runner can run half a mile in a time of 1 min and 45 s. What is the runner’s average speed in m/s?

P3.7 –(a) How many horsepower does a 100-W household lightbulb consume?

(b) How many kW does a 5-hp lawn mower engine produce?

P3.13 – Calculate the various fuel quantities for Flight 143. The plane already had 7,682 L of fuel on board prior to the flight, and the tanks were to be filled so that a total of 22,300 kg were present at takeoff.

P3.24 – When fluid flows over a surface, the Reynolds number will output whether the flow is laminar (smooth), transitional, or turbulent. Verify that the Reynolds number is dimensionless using the SI. The Reynolds number is expressed as R = pVD/µ. Where p is the density of the fluid, V is the free stream fluid velocity, D is the characteristic length of the surface, and µ is the fluid viscosity. The units of fluid viscosity are kg/(m*s).