An interactive introduction to MATLAB

72 additional exercises

whereEis the energy release by the earthquake, andE 0 = 10 4.4J is a

constant (the energy of a small reference earthquake). Determine how

many more times energy is released from an earthquake that registers

7.1 on the Richter scale than an earthquake that registers 6.9.

4. Variables
   The temperature dependence of vapor pressurepcan be estimated by
   the Antoine equation:

ln(p) =A−

B

C+T,

wherelnis the natural logarithm,pis in mm Hg,Tis in Kelvin, andA,B,

andCare material constants. For toluene (C 6 H 5 CH 3 ) in the temperature

range from 280 to 410 K the material constants are:A=16.0137,B=

3096.52, andC= −53.67. Calculate the vapour pressure of toluene at

315 and 405 K.

5. Adding vectors
   Three forces are applied to a bracket as shown in Figure 15. Determine
   the total (equivalent) force applied to the bracket.

x

y

F 1 = 400 N

F 2 = 500 N

F 3 = 700 N

20 ̊

30 ̊

143 ̊

Figure 15: Forces on a bracket