Explain slew rate and gain-bandwidth product in op-amps and their impact on circuit performance.

Slew rate is the maximum rate of change of output voltage (V/us), limiting large-signal high-frequency response. If input changes faster than slew rate allows, output distorts. Gain-bandwidth product (GBW) is constant for a given op-amp; as gain increases, bandwidth decreases proportionally. For a 1MHz GBW op-amp at gain of 10, bandwidth is 100kHz. Both parameters must be considered when selecting op-amps for high-speed or high-amplitude applications.