An electron moving in a circular orbit of radius rmakes n rotations per second. The magnetic fieldproduced at the centre has magnitude :
Magnetic field due to a circular loop
B = μ0Nl/2r Where N → no. of loops
I = q/T = e/1/n = ne
B = μ0ne/2r Here N = 1 as e makes only one loop)hence option (3)
The interference pattern is obtained with two coherent light sources of intensity ratio n. In the interference pattern, the ratio Imax-Imin/Imax+Imin will be
An air bubble in a glass slab with refractive index 1.5 (near normal incidence) is 5 cm deep when viewed from one surface and 3 cm deep when viewed from the opposite face. The thickness (in cm) of the slab is
Two identical glass (μg = 3/2) equiconvex lenses of focal length f each are kept in contact. The space between that two lenses in filled with water (μw = 4/3). The focal length of the combination is
A 100 Ω resistance and a capacitor of 100 Ω reactance are connected in series across a 220 V source. When the capacitor is 50% charged, the peak value of the displacement current is
The potential differences across the resistance, capacitance and inductance are 80 V, 40 V and 100 V respectively in an L-C-R circuit. The power factor of this circuit is
