# Random Signal MCQ [Free PDF] – Objective Question Answer for Random Signal Quiz

1. Random variables give the relationship between _____

A. Two random events
B. Probability of occurrence of two random events
C. Random event and a real number
D. Random event and its probability of occurrence

A random variable gives a functional relationship between a random event and a real number.

2. The distribution function of a  random variable is

A. P(X less than or equal to x)
B. P(X greater than or equal to x)
C. P(X less than x)
D. P(X greater than x)

The distribution function of a random variable is the probability that the value taken by the random variable is less than or equal to the real number x.

3. The distribution function of -(infinity) and (infinity) is _____

A. 0 and 1
B. 1 and 0
C. Both 0
D. Both 1

The distribution function of -(infinity) and (infinity) is 0 and 1

F(−∞) is 0 and F

(∞)) is 1.

4. The value of the probability density function of a  random variable is

A. Positive function
B. Negative function
C. Zero
D. One

The probability density function is always greater than 0. It is a non-negative function with the area of 1.

5. Which gives the measure of randomness of the random variable?

A. Mean
B. Variance
C. Standard variance
D. Pdf

Variance gives the randomness of the random variable. It is the difference between the mean square value and the square of the mean.

6. Random process is a function of ______

A. Random event and time
B. Random event and frequency
C. Random event and real number
D. None of the mentioned

A random process is a function of two variables: a random event and its time of occurrence.

7. A random process is called stationary in the  strict sense if

A. Its statistics vary with shifts in time origin
B. Its statistics do not vary with a  shift in time origin
C. Its autocorrelation varies with a  shift in time
D. Its autocorrelation does not vary with shifts in time

A random process is defined to be stationary in a strict sense if its statistics vary with a shift in time origin.

8. For a stationary process, the autocorrelation function depends on

A. Time
B. Time difference
C. Does not depend on the time
D. None of the mentioned

The autocorrelation function depends on the time difference between t1 and t2.

9. The autocorrelation function is maximum at

A. Origin
B. Infinity
C. Origin & Infinity
D. None of the mentioned

On substituting different values in the formula for autocorrelation function will be maximum at the origin.

10. Standard deviation is ______

A. Rms value of dc
B. Rms value or ac
C. Either ac or dc
D. Neither dc nor ac