One of the practical op-amp limitations is the rate at which the output voltage can change. The limiting rate of change for a device is called its "slew rate". The slew rate for the 741 is 0.5V/microsecond compared to100V/microsecond for a high-speed op-amp.
Slewing distortion
If an op amp is operated above its slew rate limit, signals will become distorted. The easiest way to see this is to look at the example of a sine wave.
Maximum rate of change of sine wave occurs at zero crossing point
Op amp slewing distortion (limit)
As can be seen in the diagram, in the limit, the op amp slewing distortion will result in the creation of a triangular waveform. If the frequency is increased the op amp will be even less able to keep up and therefore the amplitude of the output waveform will decrease.
The slew rate may also not be linear over the whole range. As a result the waveform may exhibit a faster rise for the first part of the change, then reverting to the more expected slew rate.
