The mass of a string is 5.40 10-3 kg, and it is stretched so the tension in it is 215 N. A transverse wave traveling on this string has a frequency of 260 Hz and a wavelength of 0.60 m. What is the length of the string

= 7.56 * 10^-9 W

Explanation:

1) v  =  √(T/m)

v is the velocity of a wave on the string

T is the Tension

m is the mass of a unit length ( mass of a 1 m length of the string)

   v =  f.λ

√(T/m) = fλ

√(195/m) = 260 * 0.6

we don't know m because we don't know the length

√(195 / m)    = 156  

  195/m        =  156²

  195 / m      =  24,336  

           m      =  195 / 24,336

           m      =   0.008 kg/m

now we know the mass of a unit length

m  =  M / l

M is the mass of the string

l is the length of the string

0.008 =  2.8 * 10^-3  / l

    l     =  2.8 * 10^-3 / 8 * 10-3

   l     =   2.8 / 8

   l     =  0.35 m

OK that's the answer, hope you understood.

2) Power on a unit area is 3.6 * 10^-6  W/m²

so to find the power on a specific area,  just multiply the area by the sound intensity

assuming the ear's flat area is the specified value

power intercepted by ear = (3.6 * 10^-6 W/m²) *( 2.1 * 10^-3 m²)

                                           = 7.56 * 10^-9 W

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz