PHYSICS

Class:11 P.S. #2


Q.1 Statement-1 : If the derivative of a quantity is zero, the quantity is constant.

Statement-2 : If a quantity is constant, its derivative is zero. [3]

(A) Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1.

(B) Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for statement1.

(C) Statement-1 is true, statement-2 is false.

(D) Statement-1 is false, statement-2 is true.

Paragraph for question nos. 2 to 3

When a particle is subjected to a simple harmonic motion, its x-coordinate is given by x = A sin (wt) where A and w are constants. When it is subjected to two simultaneous SHM, its x-coordinate is given by x = A sin wt + B cos wt where B is a constant.

Q.2 Which of the following quantities does not have dimensions of velocity ? [3]

(A) Aw (B) Bw (C) (D)

Q.3 The maximum x-coordinate when particle is subjected to two simultaneous SHM is [3]

(A) A + B (B) (C) A - B (D) A or B whichever is greater.

[Q.4 to Q.7 have more than one correct option]

Q.4 Figure shows a graph of x versus t for a race between a turtle and rabbit. The graph shows that [4]

(A) At the begining of race turtle was ahead of rabbit.

(B) Rabbit began to move certain time later as compared to turtle

(C) There was an interval of time when rabbit was taking rest.

(D) When rabbit was in motion at all the instants its speed was greater than that of the turtle.

Q.5 If S = _ 2 t2 + 3t + 4, then [4]

(A) at t = 1, S is local minimum (B) at t = 1, S is local maximum

(C) at t = 3, S is local maximum (D) at t = 3, S is local minimum

Q.6 The charge flowing in a conductor varies with time as Q = at _ bt2 + ct3, where a, b, c are positive constants. Then, the current i = [4]

(A) has an initial value a

(B) reaches a minimum value after time b/c

(C) reaches a maximum value after time b/c

(D) has a minimum value

Q.7 Figure shows x - t graph of a particle in rectilinear motion. Mark the correct statement(s) about the velocity in the respective region [4]

(A) AB is negative (B) OA is positive (C) OA is increasing (D) AB is decreasing



ANSWER-KEY


1 A

2 C

3 B

4 ABCD

5 BD

6 ABD

7 AB