The percentage error in the measurement of g is : (Given that $$g = {{4{\pi ^2}L} \over {{T^2}}}$$, $$L = (10\, \pm \,0.1)$$ cm, $$T = (100\, \pm \,1)$$ s)
Two very long, straight, parallel conductors A and B carry current of 5 A and 10 A respectively and are at a distance of 10 cm from each other. The direction of current in two conductors is same. The force acting per unit length between two conductors is : ($$\mu$$0 = 4$$\pi$$ $$\times$$ 10$$-$$7 SI unit)
The magnetic field on the axis of a circular loop of radius 100 cm carrying current $$I = \sqrt 2 \,A$$, at point 1 m away from the centre of the loop is given by :
At any instant, two elements X1 and X2 have same number of radioactive atoms. If the decay constant of X1 and X2 are 10 $$\lambda$$ and $$\lambda$$ respectively, then the time when the ratio of their atoms becomes $${1 \over e}$$ respectively will be :