Problem 1-11| General Principles| Engineering Mechanics: Statics| RC Hibbeler

Evaluate each of the following to three significant figures and express each answer in SI units using an appropriate prefix: (a) 354 mg (45 km)/(0.0356 kN), (b) (0.00453 Mg)(201 ms), and (c) 435 MN/23.2 mm.

Solution:

a) \frac{\left(354\:mg\right)\left(45\:km\right)}{0.0356\:kN}=\frac{\left[354\left(10^{-3}\right)\:g\right]\left[45\left(10^3\right)\:m\right]}{0.0356\:\left(10^3\right)\:N}=\frac{0.447\:\left(10^3\right)g\cdot m}{N}=0.447\:kg\cdot m/N

b) \left(0.00453\:Mg\right)\left(201\:ms\right)=\left[4.53\left(10^{-3}\right)\left(10^3\right)kg\right]\left[201\:\left(10^{-3}\right)s\right]=0.911\:kg\cdot s

c) 435\:MN/23.2\:mm=\frac{435\:\left(10^6\right)\:N}{23.2\:\left(10^{-3}\right)\:m}=\frac{18.75\left(10^9\right)\:N}{m}=18.8\:GN/m

 

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