Given below are two statements : One is labelled as Assertion \(A\) and the other is labelled as Reason R Assertion A : For measuring the potential difference across a resistance of \(600 \Omega\), the voltmeter with resistance \(1000 \Omega\) will be preferred over voltmeter with resistance \(4000 \Omega\).Reason R : Voltmeter with higher resistance will draw smaller current than voltmeter with lower resistance.In the light of the above statements, choose the most appropriate answer from the options given below
The speed of a swimmer is $4 km h ^{-1}$ in still water If the swimmer makes his strokes normal to the flow of river of width $1 km$, he reaches a point $750 m$ down the stream on the opposite bank.The speed of the river water is ___ $km h ^{-1}$
A lift of mass $M =500 kg$ is descending with speed of $2 ms ^{-1}$ Its supporting cable begins to slip thus allowing it to fall with a constant acceleration of $2 ms ^{-2}$ The kinetic energy of the lift at the end of fall through to a distance of $6 m$ will be ___ $kJ$
For hydrogen atom, $\lambda_1$ and $\lambda_2$ are the wavelengths corresponding to the transitions 1 and 2 respectively as shown in figure The ratio of $\lambda_1$ and $\lambda_2$ is $\frac{x}{32}$ The value of $x$ is
An inductor of $0.5 mH$, a capacitor of $20 \mu F$ and resistance of $20 \Omega$ are connected in series with a $220 V$ ac source If the current is in phase with the emf, the amplitude of current of the circuit is $\sqrt{x}$ A The value of $x$ is -
A thin rod having a length of \(1 m\) and area of cross-section \(3 \times 10^{-6} m ^2\) is suspended vertically from one end. The rod is cooled from \(210^{\circ} C\) to \(160^{\circ} C\) After cooling, a mass \(M\) is attached at the lower end of the rod such that the length of rod again becomes \(1m\). Young's modulus and coefficient of linear expansion of the rod are \(2 \times 10^{11} N m ^{-2}\) and \(2 \times 10^{-5} K ^{-1}\), respectively. The value of \(M\) is ____ \(kg\). (Take \(g =10 \ m s ^{-2}\))
Two identical cells, when connected either in parallel or in series gives same current in an external resistance $5 \Omega$ The internal resistance of each cell will be__ $\Omega$
Density (p) of a body depends on the force applied (F), its speed (v) and time of motion (t) by the relation p = KFavbtc , where K is a dimensionless constant. Then
A particle is projected at an angle of 30° with ground with speed 40 m/s. The speed of the particle after 2 s is (use g=10 ms-2)
A block of mass 5 kg starting from rest pulled up on a smooth incline plane making an angle of 30◦ with horizontal with an affective acceleration of 1 ms−2. The power delivered by the pulling force at t = 10 s from the starts is W. [use g=10 ms−2] (Calculate the nearest integer value)
Proton and electron have equal kinetic energy, the ratio of de-Broglie wavelength of proton and electron is \(\frac{1}{x}\). Find x. (Mass of proton 1849 times mass of electron)
Radius rA=10 cm
