Step 1: The natural frequency \( \omega_n \) of a spring-mass system is given by the formula: \[ \omega_n = \sqrt{\frac{k}{m}} \] where \( k \) is the stiffness of the spring (in N/m), and \( m \) is the mass (in kg).
Step 2: Given that the natural frequency \( \omega_n = 10 \, {rad/s} \), we can rearrange the formula to solve for the stiffness-mass relationship: \[ \omega_n^2 = \frac{k}{m} \Rightarrow k = m \omega_n^2 \] Substitute \( \omega_n = 10 \, {rad/s} \) into the equation: \[ k = m \times (10)^2 = 100m \] Step 3: Now, check each option to see which one satisfies this equation.
Option (A): If the mass is 100 kg and the stiffness is 1 N/m, then: \[ k = 100 \times 1 = 100 \, {N/m} \] But according to the formula, the stiffness should be \( k = 100 \times 100 = 10000 \, {N/m} \), so option (A) is incorrect.
Option (B): If the mass is 1.25 kg and the stiffness is 125 N/m, then: \[ k = 1.25 \times 100 = 125 \, {N/m} \] This satisfies the equation, so option (B) is correct.
Option (C): If the stiffness is 620 N/m and the mass is 6.2 kg, then: \[ k = 6.2 \times 100 = 620 \, {N/m} \] This also satisfies the equation, so option (C) is correct.
Option (D): If the stiffness is 62 N/m and the mass is 620 kg, then: \[ k = 620 \times 100 = 62000 \, {N/m} \] This does not satisfy the equation, so option (D) is incorrect.
Step 4: Therefore, the correct answers are options (B) and (C).
The figure shows a rod PQ, hinged at P, rotating counter-clockwise with a uniform angular speed of 15 rad/s. A block R translates along a slot cut out in rod PQ. At the instant shown the distance \( PR = 0.5 \, {m} \) and \( \theta = 60^\circ \). The relative velocity of R with respect to the rod PQ is 5 m/s at the instant shown. The relative acceleration of R with respect to the rod PQ is zero at the instant shown.
Which one of the following is the CORRECT magnitude of the absolute acceleration (in m/s\(^2\)) of block R?
Consider two blocks, P of mass 100 kg and Q of mass 150 kg, resting as shown in the figure. The angle \( \theta = 30^\circ \). The coefficient of friction between the two blocks is 0.2. Assume no friction exists at all other interfaces. The minimum force required to move the block P upward is \( W \). Which one of the following options is closest to the CORRECT magnitude of \( W \) (in N)?
A force of \( P = 100 \, {N} \) is applied at the ends of the pliers as shown in the figure. Neglecting friction, the force exerted by the upper jaw on the workpiece is ........... N (in integer).
Consider a beam with a square box cross-section as shown in the figure. The outer square has a length of 10 mm. The thickness of the section is 1 mm. The area moment of inertia about the x-axis is ........... mm\(^4\) (in integer).
In the figures given below, L and H indicate low and high pressure centers, respectively; PGF, CoF and CeF indicate Pressure Gradient Force, Coriolis Force and Centrifugal Force, respectively; \( V \) is Velocity. [The arrows indicate only the directions but not the magnitudes of the forces and velocity.]
Which of the following is/are the correct representation(s) of the directions of various forces and velocity in the gradient wind balance in the northern hemisphere?
Which of the following is the correct form of the mass divergence form of the continuity equation for a compressible fluid? [In the given equations, \( \rho \) is the density and \( \nabla \) the three-dimensional velocity vector of the fluid.]
[(i)] $\displaystyle \frac{\partial \rho}{\partial t} + \nabla \times (\rho \mathbf{v}) = 0$
[(ii)] $\displaystyle \frac{\partial \rho}{\partial t} + \nabla \cdot (\rho \mathbf{v}) = 0$
[(iii)] $\displaystyle \frac{\partial \mathbf{v}}{\partial t} + \rho \cdot \nabla \mathbf{v} = 0$
[(iv)] $\displaystyle \frac{\partial \rho}{\partial t} + \mathbf{v} \cdot \nabla \rho = 0$
The vertical (depth) profiles for three parameters P1, P2, and P3 in the northern Indian Ocean are given in the figure below. The values along the x-axis are the normalized values of the parameters and y-axis is the depth (m).
Identify the parameters P1, P2, and P3 from the options given below.