Exercise · ZW-IMPULSE-RESPONSE-003 · ★☆☆ Basic
If \(h[n]=0\) for \(n<0\), what property does the system have?
Choose one option.
Show answer
- C. It is causal
Explanation
An impulse response that is zero for negative times means the output does not depend on future inputs, which defines causality. The other options describe properties that do not follow from that condition.
Review the concept: Impulse response
The impulse response \(h[n]\) is the output of an LTI system when its input is the unit impulse \(\delta[n]\).
\[y[n]=\sum_{k=-\infty}^{\infty} x[k]\,h[n-k]\]
More practice problems: impulse response
- ZW-IMPULSE-RESPONSE-001 What is the output of an LTI system called when the input is δ[n]?
- ZW-IMPULSE-RESPONSE-002 What value does δ[n] take at n=0?
- ZW-IMPULSE-RESPONSE-004 If h[n] is nonzero only for n=0,1,2, what is the system called?
- ZW-IMPULSE-RESPONSE-005 Which operation combines the input x[n] with the response h[n] to produce the output?
- ZW-IMPULSE-RESPONSE-006 A system has h[n]=(0.5)^n u[n]. What is h[2]?
- ZW-IMPULSE-RESPONSE-007 For h[n]=δ[n]+2δ[n-1] and input x[n]=δ[n], what is y[1]?
- ZW-IMPULSE-RESPONSE-008 A system has h[n]=u[n]-u[n-3]. What is h[1]?
- ZW-IMPULSE-RESPONSE-009 If h[n]=δ[n-2], what output does the input x[n]=δ[n]+δ[n-1] produce at n=2?