question_answer

Two pulses travel in mutually opposite directions in a string with a  speed of 2.5 cm/s as shown in the figure. Initially the pulses are 10cm apart. What will be the state of the string after two seconds             

A)                                                                    

B)                  

C)                         

D)                  

Correct Answer: C

Solution :

                   After two seconds each wave travel a distance of 2.5 ´ 2 = 5 cm i.e. the two pulses will meet in mutually opposite phase and hence the amplitude of resultant will be zero.