PYQs Based test 4: Electromagnetic Fields

One coulomb of point charge moving with a uniform velocity 10 $\hat{x}$ m/s enters the region x ≥ 0 having a magnetic flux density$\overrightarrow{B}=\left(10y\hat{x}+10x\hat{y}+10\hat{z}\right)T$. The magnitude of force on the charge at x = 0⁺ is ______ N.

($\hat{x}$, $\hat{y}$ and $\hat{z}$ are unit vectors along x-axis, y-axis, and z-axis, respectively.)

Which one of the following vector functions represents a magnetic field $\vec{B}$ ?

(x̂, ŷ, and ẑ are unit vectors along x-axis, y-axis and z-axis, respectively)

Consider a one-turn rectangular loop of wire place in a uniform magnetic field as shown in the figure. The plane of the loop is perpendicular to the field lines. The resistance of the loop is 0.4 Ω, and its inductance is negligible. The magnetic flux density (in Tesla) is a function of time, and is given by B(t) = 0.25 sin ωt, where ω = 2π × 50 radian/second. The power absorbed (in Watt) by the loop from the magnetic field is ________.

A perfectly conduction metal plate is placed in x-y plane in a right handed coordinate system. A charge of +32πε₀√2 columbs is placed at coordinate (0, 0, 2). ϵ₀ is the permittivity of free space. Assume $\hat{i},\hat{j},\hat{k}$ to be unit vectors along x, y and z axes respectively. At the coordinate. (√2, √2, 0), the electric field vector $\vec{E}$ (Newtons/Columb) will be

Consider a large parallel plate capacitor. The gap d between the two plates is filled entirely with a dielectric slab of relative permittivity 5. The plates are initially charged to a potential difference of V volts and then disconnected from the source. If the dielectric slab is pulled out completely, then the ratio of the new electric field E2 in the gap to the original electric field E1 is ___________.