Question

5. Solve problems (a) to (c) below. (a) A 60.0-kg block is attached to a massless spring with force constant k = 575 N/m. () Find the natural frequency for this simple harmonic oscillator, in Hatz (cycles/sec). (ii) If the amplitude is 0350 m, predict the maximum speed of the block (for Instructor use only) (b) A siren has an intensity of 10W/mat a distance of 10.0 m away. What is its intensity at a distance of 5.0 m? (BONUS, +5 pts: Translate this intensity to decibels.) (c) A nylon guitar string has a lincar density of 9 50 g/m and its ends are fixed, a distance L = 95.0 cm apart. A 200 Hz oscillator is used to induce standing wave patterns in this string. Find the required tension that produces a standing wave with six antinodes

Answer 1

Mass of the object attached m = 6000 kg. spreing constant of the spreing * K = 575 Nm. (1) Angular frequeney K m 575 60 3:09 . frequency fa w=auf 21 3.09 2x3.14 = 0.49 HZ. (11) Maximum speed of the block v= СТА = 3.09 x 0.350 = 1.08 mys,

6 The total sound enerest will be remains same. 2 I ,. hari = I2 GAR? II I 2. 12 R2 TRI = 10 x 110 (10) = 40 W/m2 liner mass density of the wire . -- Р = 9.50 g/m = 9.50x103 kgfm. length of the wire. L = 95cm =0.95 m. We know v of ohl fa

T =p (62)2 Now there will be 6 antinodes. the length of the Streing Efest equal to 3d. in ) 3) L. a=t 3, P{2+2) 2 = 9,5*133 (2030 231 2 N = 38.1