Signals and Systems Quiz

Which of the following is not a continuous-time signal?

• Sin(t)

• exp(-t)

• δ[n]

• t²

The unit step function u(t) is:

• 1 for t > 0

• 0 for t > 0

• 0 for t < 0

• -1 for t < 0

A system is said to be time-invariant if:

• It produces the same output for all inputs

• Its output does not change with time

• Time shift in input causes a corresponding shift in output

• It works only in the time domain

An energy signal has:

• Infinite energy

• Finite energy and zero average power

• Infinite power

• Zero energy

Which signal is both even and periodic?

• sin(t)

• cos(t)

• exp(t)

• t

δ(t) is called:

• Unit ramp

• Unit impulse

• Step function

• Sine function

A system with memory:

• Depends only on current input

• Depends on future input

• Depends on past input

• B and C

Which operation reflects a signal about the vertical axis?

• Time scaling

• Time shifting

• Time reversal

• None

A causal system is one where:

• Output depends on future input

• Output depends only on past and present input

• Output is independent of input

• None

Even part of a signal x(t) is given by:

• x(t) - x(-t)

• [x(t) + x(-t)]/2

• [x(t) - x(-t)]/2

• x(-t)