You recently purchased a home four blocks from the busy tollway. On a typical evening, the decibel level resulting from tollway traffic is 62 dB at the location of your house. Determine the decibel level on the same evening at a house 1 block from the tollway (four times closer).

74dB

Explanation:

Sound intensity is inversely proportional to the square of the distance. Thus, a house four times closer hears a sound 16x more intense.

The dB scale is logarithmic, so 16x louder than 62 dB is equal to

62 + 10*log(16) ~= 62 + 12 = 74dB

explanation:

v=uf/(u-f)

= 5.-10/(5+10) convex lens has negative focal length

the tires are rotating at 0.434 rpmlinear speed=45 m/sdiameter=0.550 mradius=0.275 mnow v= rωω= v/rω=45/0.275ω=163.6 rad/sω=163.6 rad/s (1rev/2π rad) (60s/1m)ω=1563 rpm