JEE Advance - Physics (1998)

• 1

  Let [$${\mathrm\varepsilon}_\mathrm o$$] denote the dimentional formula of the permittivity of the vacuum, and [$$\mu_o$$] that of the permeability of the vacuum.If M = mass, L = length, T = time and I = electric current,

  回答

  B

  C
• 1

  A force $$F = - K\left( {y\widehat i + x\widehat j} \right)$$ (where K is a positive constant) acts on a particle moving in the xy plane. Starting from the origin, the particle is taken along the positive x axis to the point $$\left( {a,0} \right)$$, and then parallel to the y axis to the point $$\left( {a,a} \right)$$. The total work done by the force F on the particle is

  回答

  (C)

  $$ - K{a^2}$$
• 2

  The SI unit of inductance, the henry can be written as

  回答

  A

  B

  C

  D
• 2

  A stone tied to a string of length L is whirled in a vertical circle with the other end of the string at the center. At a certain instant of time, the stone is at its lowest position, and has a speed u. The magnitude of the change in its velocity as it reaches a position where the string is horizontal is

  回答

  (D)

  $$\sqrt {2\left( {{u^2} - gL} \right)} $$