To light, a \(50\,W , 100\,V\) lamp is connected, in series with a capacitor of capacitance \(\frac{50}{\pi \sqrt{ x }} \mu F\), with \(200 V , 50 Hz AC\) source. The value of \(x\) will be........

A capacitor of capacitance \(900\,\mu F\) is charged by a \(100\,V\) battery. The capacitor is disconnected from the battery and connected to another uncharged identical capacitor such that one plate of uncharged capacitor connected to positive plate and another plate of uncharged capacitor connected to negative plate of the charged capacitor. The loss of energy in this process is measured as \(x \times 10^{-2}\,J\). The value of \(x\) is \(..............\)

Assuming in forward bias condition there is a voltage drop of 0.7 V across a silicon diode, the current through diode \(D _1\) in the circuit is ___________mA . (Assume all diodes in the given circuit are identical)

When an external resistance of \(5\ \Omega\) is connected across terminals of a cell, a current of \(0.25\text{ A}\) flows through it. When the \(5\ \Omega\) resistor is replaced by a \(2\ \Omega\) resistor, a current of \(0.5\text{ A}\) flows through it. The internal resistance of the cell is _______ \(\Omega\).

Choose the correct option relating wavelengths of differnet parts of electromagnetic wave spectrum

Two concave refracting surfaces of equal radii of curvature and refractive index 1.5 face each other in air as shown in figure. A point object O is placed midway, between P and B . The separation between the images of \(O\), formed by each refracting surface is :

The rain drop of mass \(1\) g, starts with zero velocity from a height of \(1\) km. It hits the ground with a speed of \(5\) m/s. The work done by the unknown resistive force is _______ J. (take \(g = 10\) m/s\(^2\))

In figure \((A),\) mass ' \(2 m\) ' is fixed on mass ' \(m\) ' which is attached to two springs of spring constant \(k\). In figure \((B),\) mass ' \(m\) ' is attached to two spring of spring constant ' \(k\) ' and ' \(2 k\) '. If mass ' \(m\) ' in \((A)\) and \((B)\) are displaced by distance ' \(x\) ' horizontally and then released, then time period \(T_{1}\) and \(T_{2}\) corresponding to \((A)\) and \((B)\) respectively follow the relation.

The horizontal component of earth's magnetic field at a place is \(3.5 \times 10^{-5} \mathrm{~T}\). A very long straight conductor carrying current of \(\sqrt{2} A\) in the direction from South east to North West is placed. The force per unit length experienced by the conductor is _______ \(\times 10^{-6} \mathrm{~N} / \mathrm{m}\).

A convex lens of focal length 30 cm is placed in contact with a concave lens of focal length 20 cm. An object is placed at 20 cm to the left of this lens system. The distance of the image from the lens in cm is ________