A person travels \(x\) distance with velocity \(v_1\) and then \(x\) distance with velocity \(v_2\) in the same direction. The average velocity of the person is \(v\), then the relation between \(v , v _1\) and \(v _2\) will be :

The graph between two temperature scales \(P\) and \(Q\) is shown in the figure. Between upper fixed point and lower fixed point there are \(150\) equal divisions of scale \(P\) and \(100\) divisions on scale \(Q\). The relationship for conversion between the two scales is given by :

A planet \((P_1)\) is moving around the star of mass \(2M\) in the orbit of radius \(R\). Another planet \((P_2)\) is moving around another star of mass \(4M\) in a orbit of radius \(2R\). Ratio of time periods of revolution of \(P_2\) and \(P_1\) is _______.

A torque meter is calibrated to reference standards of mass, length and time each with \(5 \%\) accuracy. After calibration, the measured torque with this torque meter will have net accuracy of\(............\%\)

Statement\(-I :\) To get a steady de output from the pulsating voltage received from a full wave rectifier we can connect a capacitor across the output parallel to the load \({R}_{{L}}\) Statement\(-II :\) To get a steady de output from the pulsating voltage received from a full wave rectifier we can connect an inductor in series with \({R}_{{L}}\). In the light of the above statements, choose the most appropriate answer from the options given below:

A uniform disc of radius \(R\) and mass \(M\) is free to oscillate about the axis \(A\) as shown in the figure. For small oscillations the time period is ______.
(\(g\) is acceleration due to gravity)

A pendulum is suspended by a string of length \(250\,cm\). The mass of the bob of the pendulum is \(200\,g\). The bob is pulled aside until the string is at \(60^{\circ}\) with vertical as shown in the figure. After releasing the bob. the maximum velocity attained by the bob will be________ \(ms ^{-1}\). (if \(g=10\,m / s ^{2}\) )

Choose the correct option:

The \(SI\) unit of a physical quantity is pascal-second. The dimensional formula of this quantity will be ..............

An object ' \(o\) ' is placed at a distance of \(100\,cm\) in front of a concave mirror of radius of curvature \(200\,cm\) as shown in the figure. The object starts moving towards the mirror at a speed \(2\,cm / s\). The position of the image from the mirror after \(10\,s\) will be at ...... \(cm\).

Two particles move at right angle to each other. Their de Broglie wavelengths are \({\lambda _1}\) and \({\lambda _2}\) respectively. The particles suffere perfectly inelastic collision. The de Broglie wavelength \(\lambda \) , of the final particle, is given by