For an n-p-n transistor structure which of the following statements is NOT true?

A particle is exhibiting simple harmonic motion has its displacement \(x\) and velocity \(v\) related as \(4 v^2=25-x^2\). The time period of SHM is

The ground state energy of hydrogen atom is -13.6 eV . The potential energy of the electron in the first excited state of hydrogen is

A fly-wheel of mass \(25 \mathrm{~kg}\) has a radius of \(0.2 \mathrm{~m}\). It is making \(240 \mathrm{rpm}\). What is the torque necessary to bring to rest in \(20 \mathrm{~s}\) ?

A cell of emf \(10 \mathrm{~V}\) and internal resistance \(3 \Omega\) is connected in parallel with another cell of emf \(7 \mathrm{~V}\) and internal resistance \(\frac{3}{5} \Omega\), such that their positive terminals are joined together and so their are negative terminals. Their positive terminals are joined with the negative terminal and their negative terminal is joined with the positive terminal of a third cell of emf \(20 \mathrm{~V}\) with internal resistance \(2 \Omega\). The combination can be replaced by a battery of emf \(E\) and internal resistance \(r\), then the values of \(E\) and \(R\) are respectively

A convex lens of focal length 25 cm and made of glass with refractive index 1.5 is immersed in water. The absolute change in focal length of the glass is [Use refractive index of water = \(\frac{4}{3}\) ]

Consider a toroid with rectangular cross section, of inner radius \(a\), outer radius \(b\) and height \(h\), carrying \(n\) number of turns. Then the self-inductance of the toroidal coil when current \(I\) passing through the toroid is

Match the following :

Three long, straight, parallel wires carrying different currents are arranged as shown in the diagram. In the given arrangement, let the net force per unit length on the wire ' \(C\) ' be \(\vec{F}\). If the wire ' \(B\) ' is removed without disturbing the other two wires, then the force per unit length on wire ' \(\mathrm{A}\) ' is

A uniform disc of mass \(100 \mathrm{~kg}\) and radius \(2 \mathrm{~m}\) is rotating at \(1 \mathrm{rad} / \mathrm{s}\) about a perpendicular axis passing through its centre. A boy of mass \(60 \mathrm{~kg}\) standing at the centre of the disk suddenly jumps to a point which is \(1 \mathrm{~m}\) from the centre of the disc. The final angular velocity of the boy (in \(\mathrm{rad} / \mathrm{s}\) ) is

A carrier wave of peak voltage \(12 \mathrm{~V}\) is used to transmit a signal. If the modulation index is \(75 \%\), the peak voltage of the modulating signal is

An infinite line of charge with uniform line charge density of $1 \mathrm{C} {\mathrm{m}}^{-1}$ is placed along the $\mathrm{y}$-axis. A charge of $1\mathrm{C}$ is placed on the $\mathrm{x}$-axis at a distance of $d=3 \mathrm{m}$ from the origin. At what distance $\left(r\right)$ from the origin on the $\mathrm{x}$-axis, the total electric field is zero.$N$ (Assume $0<r<d$)

A glass flask of volume one litre is filled completely with mercury at \(0^{\circ} \mathrm{C}\). The flask is now heated to \(100^{\circ} \mathrm{C}\). Coefficient of volume expansion of mercury is \(1.82 \times 10^{-4} /{ }^{\circ} \mathrm{C}\) and coefficient of linear expansion of glass is \(0.1 \times 10^{-4} /{ }^{\circ} \mathrm{C}\). During this process, amount of mercury which overflows is