# National Standard Examination in Astronomy (NSEA) Solved Paper 2016 Part-7

Q: 18. Which of the following statements are true about periodic functions defined on the set of real numbers?

A : Sum of two functions with finite period is always a periodic function with finite period

B: The period of a function that is sum of two periodic functions with finite period is least common multiple of the period of two functions

(A) A and B are correct

(B) A is correct but B is incorrect

(C) A is false but B is correct

(D) A and B are false

Q: 19 Unaware about the fact that analog ammeters and voltmeters can also have zero error, a student recorded following readings while determining resistance by using Ohm’s law

 Obs. No. Voltage / V Current / mA 1 1.0 40 2 3.0 80 3 5.0 120 4 7.0 160 5 9.0 200

If the ammeter has no zero error, the zero error in the voltmeter is.

(A) -1V

(B) -1.5 V

(C) 0.5 V

(D) 1V

Q: 20 The inverse function of the function sin X + cos X is

(A)

(B)

(C)

(D)

Q: 21. Particle A collides elastically (Perfect) with particle B which was at rest. They disperse in opposite directions with same speeds. Ratio of their masses must respectively be

(A)

(B)

(C)

(D)