Eddy currents are produced in a material, when it is

The current through the circular coil is halved and the radius of the coil is doubled. If \(B_1\) and \(B_2\) are respectively the initial and final magnetic field strength, then:

A glass slab of 16 cm thickness has its bottom surface silvered. An air bubble is located inside the glass slab at a distance of 8 cm from the top surface. The refractive index of glass is 1.6. Which of the following correctly represents the number of images seen by an observer looking vertically downwards from air onto the top surface?

Specific resistance of a conductor material increases with

An unknown resistance \(R_{1}\) is connected in series with a resistance of \(10 \Omega\). This combination is connected to one gap of a meter bridge, while a resistance \(R_{2}\) is connected in the other gap. The balance point is at \(50 \mathrm{~cm}\). Now, when the \(10 \Omega\) resistance is removed the balance point shifts to \(40 \mathrm{~cm}\). The value of \(R_{1}\) (in ohm) is

A monkey of mass \(40 \mathrm{~kg}\) climbs up a rope which can stand a maximum tension of \(600 \mathrm{~N}\). The rope will break, when the monkey

If \(120 \mathrm{~J}\) of work is done in \(2 \mathrm{~min}\) by a water pump, then the power of the pump is

An alkyl halide reacts with alcoholic ammonia in a sealed tube, the product formed will be

A body is projected vertically upwards. The times corresponding to height \(h\), while ascending and while descending are \(t_{1}\) and \(t_{2}\), respectively. Then, the velocity of projection is ( \(g\) is acceleration due to gravity)

Using the data given below, the strongest reducing agent is:
\(E^o_{\text{Cr}_2\text{O}_7^{2-}/\text{Cr}^{3+}} = 1.33\) V    \(E^o_{\text{MnO}_4^-/\text{Mn}^{2+}} = 1.51\) V
\(E^o_{\text{Cl}_2/\text{Cl}^-} = 1.36\) V    \(E^o_{\text{Cr}^{3+}/\text{Cr}} = -0.74\) V

A particle \(A\) has charge \(+q\) and particle \(B\) has charge \(+4 q\), each of them having the same mass \(m\). When allowed to fall from rest through the same electrical potential difference, then the ratio of their speeds will become

A point marked on a ring of radius 2 cm is in contact with a horizontal plane. Now the ring is rolled forward half a revolution along the positive X - direction. Then the angle made by the displacement vector of the point with the X - axis is:

Match the reaction in Column I with the major product formed given in Column II.
\(\begin{array}{|l|l|l|} \hline & \text { Column I- Reaction/conditions } & & \text { Column II- Product } \\ \hline A & \mathrm{C}_6 \mathrm{H}_6 \xrightarrow[\substack{\text{(ii) NaOH} \\ \text{(iii) H^+}}]{\text{(i) Oleum}} & P & \text { Pentan-2-ol. } \\ \hline B & \text{Butanal } \xrightarrow[\text{(ii) } \mathrm{H}^+]{\text{(i) } \text{MeMgBr/ dry ether}} & Q & \text { 2-Hydroxybenzoic acid. } \\ \hline C & \text {2-Methylpropene } \xrightarrow[\text { (ii) } \mathrm{H}_2 \mathrm{O}_2 / \mathrm{NaOH}]{\text { (i) } \mathrm{B}_2 \mathrm{H}_6} & R & \text { Phenol } \\ \hline D & \text{Phenol } \xrightarrow[\text { (ii) } \mathrm{CO}_2, 400 \mathrm{~K}, 7 \mathrm{~atm} .]{\text { (i) } \mathrm{NaOH}} & S & \text { 2-Methylpropan-1-0 I } \\ \hline \end{array}\)