Physics

This problem is about recognizing that a wave pulse's shape is encoded in how the argument $(x - 2t)$ changes with time. The key insight is that $(x - 2t) = \text{constant}$ traces out the pulse's motion: as $t$ increases, the entire profile shifts rightward at speed $v = 2$ cm/s. Rather than deriving anything, you're just evaluating the same function at three different times and watching how the bump translates along the string—this visual approach makes wave propagation concrete.

This problem is about recognizing that a wave pulse's shape is encoded in how the argument $(x - 2t)$ changes with time. The key insight is that $(x - 2t) = \text{constant}$ traces out the pulse's motion: as $t$ increases, the entire profile shifts rightward at speed $v = 2$ cm/s. Rather than deriving anything, you're just evaluating the same function at three different times and watching how the bump translates along the string—this visual approach makes wave propagation concrete.