41.  The force acting between two point charges kept at a certain distance is $$F_{1}$$ Now magnitude of charge are double and distance between them is double. The force acting between them is $$F_{2}$$ find out the ratio of $$\frac{F_{2}}{F_{1}}=\ ?$$

A. 16 : 1

B. 1 : 16

C. 1 : 1

D. 1 : 8

Explanation :

$$F_{1}=\frac{kq_{1}q_{2}}{r_{1}^{2}}$$, $$F_{2}=\frac{kq_{1}q_{2}}{r_{2}^{2}}$$

42.  If the resulting external force acting on system is zero then _______ of the system is constant and if the resultant external torque acting on a system is zero then _______ of the system is constant.

A. total energy, angular momentum

B. liner momentum, angular momentum

C. liner momentum, energy

D. angular and linear momentum

43.  Space is homogeneous and isotropic so ________ law of servation is the result of this

A. linear and angular momentum

B. angular and linear momentum

C. energy and charge

D. charge and energy

44.  Time is homogeneous so _________ law of conservation is the result of this

A. angular momentum

B. linear momentum

C. energy

D. charge

45.  The basic reason behind existence of which conservation of law is still not known ?

A. angular momentum

B. linear momentum

C. energy

D. charge

46.  The Gravitational force between any two body charges with distance as $$F\alpha\ r^{n}$$ where n = _____

A. -1

B. 2

C. -3

D. -2

47.

Match the column

Column - I                               Column - II

(1) space is isotropic               (P)conservation of linear momentum

(2) space is homogeneous      (Q)conservation of energy

(3) Time is homogeneous       (R)conservation of charge still not known

(4) Time is isotropic                (S)conservation of angular momentam

A. 1-(S), 2-(P), 3-(R), 4-(Q)

B. 1-(S), 2-(P), 3-(Q), 4-(R)

C. 1-(P), 2-(S), 3-(R), 4-(Q)

D. 1-(R), 2-(Q), 3-(P), 4-(S)

48.  Which of the following unit is not of length ?

A. Light year

B. Fermi

C. Angstrom

D. Becquerel

49.  Becquerel is a ________ unit and its symbol is _______

A. supplementary, Bq

B. fundamental, Bq

C. derived, Bq

D. derived, Bv