Giancoli Ch 15-17 Vibrations on steel wire under tension. Assign given values.
Twire .4.5 newton dwire .1 mm f .60 Hz ρ steel .7.8 gm cm. 3. (You have to look ...
Giancoli Ch 15-17 Vibrations on steel wire under tension. Assign given values. T wire f
4.5 . newton
60 . Hz
D wire
d wire
1 . mm
ρ steel
7.8 .
gm cm3
(You have to look up density of steel)
0.5 . cm
Calculate the density of the wire. d wire 2
A wire
π.
µ wire
ρ steel . A wire
2
3
µ wire = 6.126 10
kg m
(a) Find power in the wave. First, calculate the wave speed. v wire
T wire µ wire
v wire = 27.103
m sec
Use Eq. 15-7 to find intensity and hence power. P
A wire . 2 . π 2 . v wire . ρ steel . f2 . D wire2
P = 0.295 watt (b) Doubling the frequency would quadruple the power all things being equal. Since power is also proportional to amplitude squared, halving the amplitude would bring the power back to the original level, hence D M=.5cm/2=0.25 cm.
