Question

Anthony sends a series of pulses of amplitude 43 cm down a string that is attached to a post at one end. Assume the pulses are reflected with no loss of amplitude.(a) What is the amplitude at a point where two pulses are crossing if the string is rigidly attached to the post?cm(b) What is the amplitude at a point where two pulses are crossing if the end at which reflection occurs is free to slide up and down?cm

Answer 1

(A) 0 cm

(B) 86 cm

Step-by-step explanation:

(A) Since the string is rigidly attached to the post, the interference at the point where the two pulses are crossing will be a destructive one and hence the amplitude will be 0 cm

(B) Since the string is free to slide up and down, the interference at the point where the two pulses are crossing will be a constructive one and hence the amplitude will be doubled = 43 x 43 = 86 cm