A pulse in a light string (String 1) travels toward a junction with a medium-weight…
PHYSICS · Single correct · A Level · Physics · Waves · Waves
Problem
A pulse in a light string (String 1) travels toward a junction with a medium-weight string (String 2). Immediately after that junction, String 2 is spliced to a very heavy rope (String 3). The relative impedances satisfy Z1≪Z2≪Z3.
After the pulse passes both junctions, three distinct pulses can be observed:
• R1: the pulse reflected back into String 1 at the first junction
• R2: the pulse reflected back into String 2 at the second junction
• T: the pulse transmitted forward into String 3
Which ranking correctly orders the intensities of these three pulses from greatest to least?
(a) R1>T>R2
(b) R2>R1>T
(c) R1>R2>T
(d) T>R1>R2