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The general ordering of the electromagnetic spectrum from shortest to longest wavelength is as follows: 1. Gamma rays 2. X-rays 3. Ultraviolet (UV) rays 4. Visible light 5. Infrared (IR) radiation 6. Microwaves 7. Radio waves Therefore, X-rays are the correct answer.

Standing waves are formed when waves reflect back from a boundary and interfere with the incoming waves of the same frequency and amplitude, creating points that appear to stand still (nodes) and points of maximum oscillation (antinodes).

Water waves are mechanical waves that require a material medium, such as water, to propagate. They involve the vibration of water particles. In contrast, light waves are electromagnetic waves that do not need a medium for propagation; they can travel through a vacuum. For example, sunlight travels through space without the need for any material medium.

Answer: A. 1:4 (Pressure equal: \(\frac{F_1}{(\pi r_1^2)}\) = \(\frac{F_2}{(\pi r_2^2)}\); \(\frac{_r2}{r_1}\) = \(\sqrt{(F_2}{F_1)}\) = \(\sqrt{16}\) = 4.)

Answer: B For equilibrium, clockwise moment = anticlockwise moment about the pivot. clockwise distance from pivot: 50cm - 10cm = 40cm anticlockwise distance from pivot: 85cm - 10cm = 75cm Applying the principle of moments W x distance(w) = T x distance(T) 100 x 40 = T x 75 T = \(\frac{ 4000}{75}\) ≈ 53.33N

T x 80 + 15 x 10 = W x 50 80T + 150 = 50W - - -- - - - - -(1) T + 15 = W - - - - - - - - - - - (2) 80T + 150 = 50(T + 15) 80T + 150 = 50T + 750 30T = 750 - 150 30T = 600 T = 20N The closest option is 19.2N

C. 6 kg Initial velocity \( u = 4 \, \text{m/s} \), Acceleration \( a = 5 \, \text{m/s}^2 \), Time \( t = 2 \, \text{s} \) Final velocity: \(v = u + at = 4 + 5 \times 2 = 14 \, \text{m/s}\) Change in momentum (impulse): \(\Delta p = m(v - u) = 60\) Substituting for \( v \): \(m(14 - 4) = 60\) Simplifying: \(m \times 10 = 60\) Thus, \(m = 6 \, \text{kg}\)

A. Q In a simple pendulum, kinetic energy is maximum at the lowest point (equilibrium position) where potential energy is minimum and speed is maximum.Here, Q is the control point (mean/equilibrium position), so maximum kinetic energy occurs at Q. At extremes P and S, kinetic energy is zero (velocity = 0). At R, it is between the extreme and the equilibrium.

The frequency \( f \) of a simple pendulum is: \(f = \frac{1}{2\pi} \sqrt{\frac{g}{L}} \quad \text{where } L = 1.2 \, \text{m}, \, g = 10 \, \text{m/s}^2, \, \pi \approx \frac{22}{7}\) Calculate: \(\frac{g}{L} = \frac{10}{1.2} = \frac{25}{3}, \quad \sqrt{\frac{25}{3}} = \frac{5}{\sqrt{3}}\) \(f = \frac{1}{2 \times \frac{22}{7}} \times \frac{5}{\sqrt{3}} = \frac{35}{44\sqrt{3}}\) Approximating \( \sqrt{3} \approx 1.732 \): \(44 \times 1.732 \approx 76.208 \quad \Rightarrow \quad \frac{35}{76.208} \approx 0.459 \, \text{Hz}\) Thus, the answer is \( D. \, 0.5 \) Hz.

Answer: B. 0.015 (Net F = ma = 40\times0.3 = 12 N; friction = 18 - 12 = 6 N; \mu = \(\frac{\text{friction}}{\text{mg}}\) = \(\frac{6}{(40\times10)}\) = 0.015.)

Frictional force is the tangential force opposing an object's free sliding on an adjacent surface. It originates from surface irregularities and intermolecular attractions between materials, resisting relative motion or its initiation.

Given: g = 9.8 m/s\(^2\), a = 10 m/s, v = 0( come to rest), s = 25m v\(^2\) = u\(^2\) + 2as - 100 = 2 x 25 x a a = \(\frac{-100}{50}\) = - 2 deceleration is caused by kinetic friction But, \(\mu\) = \(\frac{\text{f}}{\text{R}}\) = \(\frac{\text{ma}}{\text{mg}}\) = \(\frac{-2}{9.8}\) ≈ 0.2.

The net force (\(F_{\text{net}}\)) is the weight (\(W\)) minus the total upward forces (upthrust (\(U\)) and viscous drag (\(F_{\text{drag}}\))), and this net force causes the acceleration (\(a\)) according to Newton's second law (\(F_{\text{net}}=ma\)): \(F_{\text{net}} = W - U - F_{\text{drag}}\) \(ma = (m \times g) - U - F_{\text{drag}}\) \((10\text{ kg}) \times a = (10\text{ kg} \times 10\text{ m/s}^{2}) - 10\text{ N} - 15\text{ N}\) \(10a = 100\text{ N} - 25\text{ N}\) \(10a = 75\text{ N}\) \(a = \frac{75\text{ N}}{10\text{ kg}}\) \(a = 7.5\text{ m/s}^{2}\).

Answer: C Fraction immersed = \(\frac{\text{density of block}}{\text{density of liquid}}\) = \(\frac{400}{1600}\) = 0.25.

The elastic potential energy \( E \) is proportional to the square of the force: \(E \propto F^2\) (for the same spring). The relationship between the energies for different forces is given by: \(\frac{E_2}{E_1} = \left( \frac{F_2}{F_1} \right)^2\) Now, substituting the known values: \(E_2 = 0.16 \times \left( \frac{700}{200} \right)^2 = 0.16 \times (3.5)^2 = 0.16 \times 12.25 = 1.96 \, \text{J}\)