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When the prongs of the tuning fork are loaded, it causes an increase in their inertia, thereby decreasing the frequency of the fork.

v = 2.5u F = \(\frac {uv}{u + v}\) 0.2 = \(\frac {u \times 2.5u}{u + 2.5u}\) u = 0.28m

F = \(\frac{uv}{u + v}\) 15 = \(\frac{10 \times v}{10 + v}\) v = -30cm

No expanded working has been attached for this question yet. The verified answer is Option A.

Wavelength Order: In the visible spectrum, the order of colors from shortest to longest wavelength is as follows: violet, blue, green, yellow, orange, and red. Therefore, violet light has the shortest wavelength, making it the first color in the spectrum when white light is dispersed.

Ultra-violet (UV) rays have shorter wavelengths than infra-red (IR) rays. This is correct. In the electromagnetic spectrum: UV → shorter wavelength than visible light Visible light → in the middle IR → longer wavelength than visible light So, UV has a much shorter wavelength than IR. - UV rays produce fluorescence. This is also correct. Ultraviolet rays are well-known for causing certain materials (like fluorescent dyes, whitening agents, or minerals) to glow or emit visible light — this is called fluorescence. It's commonly used in black lights, forensic science, etc.

No expanded working has been attached for this question yet. The verified answer is Option C.

No expanded working has been attached for this question yet. The verified answer is Option D.

From, the above figure @ M\(_2\), i = r = 60º

No expanded working has been attached for this question yet. The verified answer is Option C.

(a)(i) When the parallel rays of light from the sun pass through the converging lens, they converge at the principal focus. This converging rays cause the paper to ignite after a while. (ii) Production of an enlarged picture as in the magnifying glass. I - enlarged image; O - object. Alternatively, as in the slide projector below The lens causes the image to be magnified but inverted in this case. (iii) Correction of eye defect: Converging lens can be used for correcting long sightedness. Long sightedness occurs when the eyeball is too short. Rays from the normal near point (25cm from the eye) are brought to focus beyond the eyeball instead of on the retina. The correction is done as shown below. (b) A mechanical wave is one that requires material medium for their propagation e.g. sound waves, water waves. Waves which do not require material medium for their propagation i.e. they can pass through vacuum are electromagnetic waves. Experiment to show that sound requires material medium for transmission. When the key is closed, current will flow through the electric bell and the hammer will be seen, striking the gong. Sound will thus be produced. However as the air inside the bell jar is gradually pumped out using a vacuum pump via the opening, the intensity of the sound produced by the electric bell gradually dies down even though the hammer is still seen striking the gong. When the air has been pumped out and the bell jar becomes empty (vacuum), the intensity of the sound dies almost completely. This shows that sound requires a material medium (air in this case) for transmission. The three characteristics of sound are: 1. Intensity or Loudness: depends on amplitude. 2. Pitch : depends on frequency 3. Quality or Timbre : depends on overtones.

No expanded working has been attached for this question yet. The verified answer is Option B.

F = \(\frac{1}{2L}\sqrt\frac{T}{m}\)

n = \(\frac{360}{\theta}\) - 1 = \(\frac{360}{90}\) - 1 = 3 images

F = \(\frac{UV}{U + V}\) 20 = \(\frac{60 \times V}{60 + V}\) V = 30cm similarly, \(\frac{U}{V}\) = \(\frac{\text{height of object}}{\text{height of image}}\) \(\frac{60}{30}\) = \(\frac{3}{h}\) h = 1.5cm