A tightly wound 100 turns coil of radius $$10 \mathrm{~cm}$$ carries a current of $$7 \mathrm{~A}$$. The magnitude of the magnetic field at the centre of the coil is (Take permeability of free space as $$4 \pi \times 10^{-7} \mathrm{SI}$$ units):
A parallel plate capacitor is charged by connecting it to a battery through a resistor. If $$I$$ is the current in the circuit, then in the gap between the plates:
A long straight wire of length $$2 \mathrm{~m}$$ and mass $$250 \mathrm{~g}$$ is suspended horizontally in a uniform horizontal magnetic field of $$0.7 \mathrm{~T}$$. The amount of current flowing through the wire will be $$\left(\mathrm{g}=9.8 \mathrm{~ms}^{-2}\right)$$ :
A uniform electric field and a uniform magnetic field are acting along the same direction in a certain region. If an electron is projected in the region such that its velocity is pointed along the direction of fields, then the electron: