List of practice Questions

A beam of light falls on a metal surface such that photo-electrons are generated. If the power of the light source starts to decrease linearly with time, then the variation of the photocurrent \(I\) and magnitude of the stopping potential \(|V|\) with time is best represented by :

In the measurement of viscosity of liquids using terminal velocity experiment, spherical balls of same radius but having different densities are used. The variation of the terminal velocity (\(v\)) with the ratio of density of spherical ball (\(\sigma\)) to density of the liquid (\(\rho\)), is best represented by:

An ideal Zener diode with breakdown voltage of \(3\,\text{V}\) is reverse biased with a negative input voltage \(V_1=-5\,\text{V}\). The magnitude of voltage difference between points \(B\) and \(A\) is:

Two planets \(P_1\) and \(P_2\) with equal mass have radii \(R_1\) and \(R_2\), respectively, where \[ R_2=\frac{R_1}{2} \] The escape speeds of \(P_1\) and \(P_2\) are \(v_1\) and \(v_2\), respectively. Then the value of \[ \frac{v_2}{v_1} \] is:

Water flows in a streamline motion through a horizontal pipe of circular cross-section as shown in the figure. The pressure difference of water between \(P\) and \(Q\) is \(15\,\text{N m}^{-2}\). The area of cross-section at \(P\) and \(Q\) are \(40\,\text{cm}^2\) and \(20\,\text{cm}^2\), respectively. The rate of flow of water through the pipe, in \(\text{cm}^3\text{s}^{-1}\), is:

A thin horizontal disc is rotating about a vertical axis passing through its fixed centre \(O\). Its angular momentum is \(L_A\) and \(L_B\) computed about points \(A\) and \(B\), respectively, where \(OB=2\times OA\). The value of \[ \frac{L_A}{L_B} \] is:

Consider a long solenoid of length \(l\) and radius \(r\). If \(n\) is the number of turns per unit length and \(\mu_0\) is the permeability of free space, the inductance of the solenoid is:

The temperature of a metallic sphere of radius \(R\) is increased by a small amount \(\Delta T\). If the linear coefficient of thermal expansion of the metal is \(\alpha\), the approximate increase in the volume of the sphere is:

A photon and an electron, each of \(10\,\text{eV}\) energy, move in free space. The ratio of linear momentum of electron \(P_e\) to that of photon \(P_{ph}\), \[ \frac{P_e}{P_{ph}} \] is :

Goods that are used by producers as inputs

The number of critical points of the function} \[ f(x)= \begin{cases} \dfrac{|\sin x|}{x}, & x\neq0\\ 1, & x=0 \end{cases} \] in the interval \((-2\pi,2\pi)\) is equal to:

The number of hydrogen atoms present in \(5.4\text{ g}\) of urea is: \[ \text{Given: Molar mass of urea }=60\text{ g mol}^{-1} \] \[ N_A=6.022\times10^{23}\text{ particles mol}^{-1} \]

An electron falls through a distance 1.5 cm in a uniform electric field of magnitude 2.0 \(\times\) 10\(^4\) N/C from rest. The time taken to cover this distance in second is \textunderscore\textunderscore\textunderscore\textunderscore\textunderscore.
(e = 1.6 \(\times\) 10\(^{-19}\) C, m\(_e\) = 9.11 \(\times\) 10\(^{-31}\) kg)

The power of a crane, which lifts a mass of 1000 kg to a height of 20 m in 10 s is: (g = 9.8 m/s²)

If $P = \begin{pmatrix} 1 & \alpha & 3 \\ 1 & 3 & 3 \\ 2 & 4 & 4 \end{pmatrix}$ is the adjoint of a $3 \times 3$ matrix A and $det(A) = 4$, then $\alpha =$

Which of the following pairs contains only intensive properties?

The major product formed in the following reaction is p

Given below are four sentences. Choose the one which is grammatically correct:

Let \( A = \begin{bmatrix} 1 & 2 2 & 1 \end{bmatrix} \) and \( B = \begin{bmatrix} x & y 1 & 2 \end{bmatrix} \) be two matrices such that \( (A + B)(A - B) = A^2 - B^2 \).
If \( C = \begin{bmatrix} x & 2 1 & y \end{bmatrix} \), then trace \((C) = \)

A ray of monochromatic light is passing through an equilateral prism (ABC) as shown in the figure. The refracted ray (QR) is parallel to its base (BC) and the angle of incidence (i) is 50°. Then the angle of deviation ($\delta$) is: ____.

Bile is produced in which part of the body?

An equilateral triangle OAB is inscribed in the parabola $y^2 = 4x$ with the vertex O at the vertex of the parabola. Then the minimum distance of the circle having AB as a diameter from the origin is

The least possible level of sensation is called as _______