As heat is taken away from a fluid, its particles. slow down and come closer together. ï®. This causes the fluid to contract â its volume. decreases. ï®. This causes the density to increase. (D=M/V if V gets smaller, M/V gets bigger) ï®. Viscosity will also be affected, as particles slow. down and come closer together, it gets harder. for them to move past each other. Therefore, viscosity increases.
The commercial kind are probably $250 on up. You can get a nice Shure brothers mike for around $120. Their SM-58 is good for recording and amplifying voices, and the SM-57 excels at recording or amping musical instruments. Sennheiser is a long-time company that also makes several lines of mikes (or mics, if you prefer) that range from home-use to phenomenal studio use.
1 Behind-the-ear (BTE) hearing aids cost between $450 and $5,600. 2  Economy Hearing Products offers a very basic BTE hearing aid for about $630. 3  ReSound Azure retails for about $2,600 with programmable volume control settings, an open fit to minimize a plugged up sensation in the ear and a 330-hour battery. Patients also need a hearing aid selection appointment, which can be free with purchase or cost up to $250, depending upon the clinic. 2  The Cleveland Clinic charges about $100 for hearing needs assessment. 3  There are several different types of hearing aids.