For a series RLC circuit R = XL =  2Xc. The impedance of the circuit and phase difference between V and I respectively will be

A) $\frac{\sqrt{5}r}{2}$, $\tan^{-1}$(2)

B) $\frac{\sqrt{5}r}{2}$, $\tan^{-1}$ $\frac{1}{2}$

C) $\sqrt{5X_{c}}$, $\tan^{-1}$(2)

D) $\sqrt{5R}$, $\tan^{-1}$ $\frac{1}{2}$


A particle having a mass of 0.5 kg is projected under gravity with a speed of 98 m/sec at an angle of 60°. The magnitude of the change in momentum (in N-sec) of the particle after 10 seconds is [g = 9.8 m/sec2]

A) 0.5

B) 49

C) 98

D) 490


A metal ring is held horizontally and the bar magnet is dropped through the ring with its length along the axis of the ring. The acceleration of the falling magnet

A) is equal to g

B) is less than g

C) is more than g

D) depends on the diameter of ring and length of magnet


A particle covers half of the circle of radius r. Then the displacement and distance of the particle are respectively

A) $2\pi r, 0$

B) $2r, \pi r$

C) $\frac{\pi r}{2}$, 2r

D) $\pi r, r$


ln an electromagnetic wave

A) power is transmitted along the magnetic field

B) power is transmitted along the electric field

C) power is equally transferred along the electric and magnetic fields

D) power is transmitted in a direction perpendicular to both the fields