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The length of a magnetized iron bar is $L$ and its magnetic moment is $M$. When this bar is bent to form a semicircle its magnetic moment is:
The bulk modulus of a spherical object is $B$. If it is subjected to uniform pressure $P$, the fractional decrease in radius will be:
A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It:
A solid sphere is rotating freely about its symmetry axis in free space. The radius of the sphere is increased keeping its mass same. Which of the following physical quantities would remain constant for the sphere?
A convex lens and a concave lens, each having the same focal length of $25\text{ cm}$, are put in contact to form a combination of lenses. The power in dioptres of the combination is:
Select the correct option based on the statements: Statement I: The magnetic field of a circular loop at very far away point on the axial line varies with distance as like that of a magnetic dipole. Statement II: The magnetic field due to magnetic dipole varies inversely with the square of the distance from the centre on the axial line.
A soap bubble, having radius of $1\text{ mm}$, is blown from a detergent solution having a surface tension of $2.5 \times 10^{-2}\text{ N/m}$. The pressure inside the bubble equals at a point $Z_0$ below the free surface of water in a container. Taking $g = 10\text{ m/s}^2$, density of water $= 10^3\text{ kg/m}^3$, the value of $Z_0$ is :
Two racing cars of masses $m_1$ and $m_2$ are moving in circles of radii $r_1$ and $r_2$ respectively. Their speeds are such that each makes a complete circle in the same duration of time $t$. The ratio of the angular speed of the first to the second car is:
Match List-I with List-II. **List-I (Material)** (A) Diamagnetic (B) Ferromagnetic (C) Paramagnetic (D) Non-magnetic **List-II (Susceptibility $\chi$)** (I) $\chi = 0$ (II) $0 > \chi \ge -1$ (III) $\chi \gg 1$ (IV) $0 < \chi < \epsilon$ (a small positive number) Choose the correct answer from the options given below:
A wire of length $L$, area of cross section $A$ is hanging from a fixed support. The length of the wire changes to $L_1$ when mass $M$ is suspended from its free end. The expression for Young's modulus is:
A 150 m long train is moving to north at a speed of 10 m/s. A parrot flying towards south with a speed of 5 m/s crosses the train. The time taken by the parrot to cross the train would be:
The angular speed of the seconds needle in a mechanical watch is:
In a uniform magnetic field of $0.049 \text{ T}$, a magnetic needle performs $20$ complete oscillations in $5$ seconds as shown. The moment of inertia of the needle is $9.8 \times 10^{-6} \text{ kg m}^2$. If the magnitude of magnetic moment of the needle is $x \times 10^{-5} \text{ Am}^2$, then the value of '$x$' is:
A stone tied to the end of a string of 1 m long is whirled in a horizontal circle with a constant speed. If the stone makes 22 revolutions in 44 s, what is the magnitude and direction of acceleration of the stone?
The maximum number of electrons in a subshell with l = 3 and n = 4 is:
At point A on the earth's surface, the angle of dip is, $\delta=+25^\circ$. At a point B on the earth's surface, the angle of dip is, $\delta=-25^\circ$. We can interpret that:
The magnitude and direction of the current in the following circuit is
The following four wires are made of the same material. Which of them will have the largest extension when the same tension is applied?
What is the value of linear velocity if $\vec{\omega} = 3\hat{i} - 4\hat{j} + \hat{k}$ and $\vec{r} = 5\hat{i} - 6\hat{j} + 6\hat{k}$:
A ball is thrown upwards and it returns to the ground describing a parabolic path. Which of the following remains constant?