1. Q14.Wave Motion

2. 1.The displacement of a string carrying a traveling sinusoidal wave is given by 1. v 0 /  y 0 2.  y 0 / v 0 3.  v 0 / y 0 4. y 0 /  v 0 5.  v 0 y 0 At time t  0 the point at x  0 has velocity v 0 and displacement y 0. The phase constant  is given by tan   :

3. 1.The displacement of a string carrying a traveling sinusoidal wave is given by At time t  0 the point at x  0 has velocity v 0 and displacement y 0. The phase constant  is given by tan   :

4. 2.The diagram shows three identical strings that have been put under tension by suspending masses of 5 kg each. For which is the wave speed the greatest ? 1. 1 2. 2 3. 3 4. 1 and 3 tie 5. 2 and 3 tie

5.  Larger T  larger v Ans: 1 & 3 tied

6. 3.The tension in a string with a linear density of 0.0010 kg/m is 0.40 N. A 100 Hz sinusoidal wave on this string has a wavelength of : 1. 0.05 cm 2. 2.0 cm 3. 5.0 cm 4. 20 cm 5. 500 cm

7. 3.The tension in a string with a linear density of 0.0010 kg/m is 0.40 N. A 100 Hz sinusoidal wave on this string has a wavelength of :

8. 4.Suppose the maximum speed of a string carrying a sinusoidal wave is v s. When the displacement of a point on the string is half its maximum, the speed of the point is : 1. v s / 2 2. 2 v s 3. v s / 4 4. 3 v s / 4 5.  3 v s / 2

9.   4.Suppose the maximum speed of a string carrying a sinusoidal wave is v s. When the displacement of a point on the string is half its maximum, the speed of the point is :

10. 5.Two sinusoidal waves have the same angular frequency, the same amplitude y m, and travel in the same direction in the same medium. If they differ in phase by 50°, the amplitude of the resultant wave is given by : 1. 0.64 y m 2. 1.3 y m 3. 0.91 y m 4. 1.8 y m 5. 0.35 y m

11.  Amplitude  5.Two sinusoidal waves have the same angular frequency, the same amplitude y m, and travel in the same direction in the same medium. If they differ in phase by 50°, the amplitude of the resultant wave is given by :

12. 6.The sinusoidal wave y(x,t)  y m sin( k x –  t ) is incident on the fixed end of a string at x  L. The reflected wave is given by : 1. y m sin( k x +  t ) 2. –y m sin( k x +  t ) 3. y m sin( k x +  t – k L ) 4. y m sin( k x +  t – 2 k L ) 5. –y m sin( k x +  t + 2 k L )

13. Let the time of incidence be t 0  6.The sinusoidal wave y(x,t)  y m sin( k x –  t ) is incident on the fixed end of a string at x  L. The reflected wave is given by :

14. 7.Standing waves are produced by the interference of two traveling sinusoidal waves, each of frequency 100 Hz. The distance from the 2nd node to the 5th node is 60 cm. The wavelength of each of the two original waves is : 1. 50 cm 2. 40 cm 3. 30 cm 4. 20 cm 5. 15 cm

15. In order to have a standing wave, these waves must travel in opposite directions. Distance from the 2nd node to the 5th node is 60 cm :  7.Standing waves are produced by the interference of two traveling sinusoidal waves, each of frequency 100 Hz. The distance from the 2nd node to the 5th node is 60 cm. The wavelength of each of the two original waves is :

16. 8.A stretched string, clamped at its ends, vibrates in its fundamental frequency. To double the fundamental frequency, one can change the string tension by a factor of : 1. 2 2. 4 3.  2 4. 1 / 2 5. 1 /  2

17. Clamped at ends & fundamental mode  fixed 8.A stretched string, clamped at its ends, vibrates in its fundamental frequency. To double the fundamental frequency, one can change the string tension by a factor of :

18. 9.A 40-cm long string, with one end clamped and the other free to move transversely, is vibrating in its fundamental standing wave mode. If the wave speed is 320 cm/s, the frequency is : 1. 32 Hz 2. 16 Hz 3. 8 Hz 4. 4 Hz 5. 2 Hz

19. One end clamped and the other free to move transversely. Fundamental standing wave mode   4 L. 9.A 40-cm long string, with one end clamped and the other free to move transversely, is vibrating in its fundamental standing wave mode. If the wave speed is 320 cm/s, the frequency is :