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When the hole of a pinhole camera is diminished, the image becomes II sharp. A smaller aperture reduces the amount of light entering, leading to a sharper image, but it also requires more light for proper exposure.

Under blue light, a red rose will appear black or very dark. This is because the red pigments in the rose reflect red light and absorb other colors. Since blue light does not contain red wavelengths, no light is reflected back to the observer, causing the rose to appear dark.

Refractive index = \(\frac{\text{real depth}}{\text{apparent depth}}\) Real depth = refractive index x apparent depth Apparent depth = 10cm Refractive index = 1.33 Real depth = 1.33 x 10 = 13.3cm.

distance between two successive crests of a water wave = \(\lambda\) = 0.25m Frequency (f) is defined as the number of cycles or oscillations that occur in one second = four complete vertical oscillations in one second = 4Hz Speed of wave (v) = f x \(\lambda\) = 0.25 x 4 = 1m/s

For a sonometer, F \(\propto\) \(\sqrt{T}\) F = k \(\sqrt{T}\) F\(_1\) = 50Hz, F\(_2\) = ? T\(_1\) = T, T\(_2\) = 4T \(\frac{F_1}{\sqrt{T_1}} = \frac{F_2}{\sqrt{T_2}}\) \(\frac{50}{\sqrt{T}} = \frac{F_2}{\sqrt{4T}}\) F\(_2\) = \(\frac{50 \times 2 \times\sqrt{T}}{\sqrt{T}}\) F\(_2\) = 100Hz

Beat frequency = f\(_1\) - f\(_2\) f\(_1\) = 6Hz f\(_2\) = 4Hz Beat frequency = f\(_1\) - f\(_2\) = 6 - 4 = 2Hz

For a closed pipe, only odd harmonics are present. first overtone frequency is 3f\(_o\), 2\(^{nd}\) overtone frequency is 5f\(_o\) etc. 4\(^{th}\) overtone frequency = 9f\(_o\) 900 = 9f\(_o\) f\(_o\) = \(\frac{900}{9}\) = 100Hz

Presbyopia: Caused by aging and weakened ciliary muscles, making it hard to focus on nearby objects.

Presbyopia is the condition where the eye's ability to focus on close objects decreases with age, and bifocal lenses provide two different optical powers for distance and near vision.

POWER = \(\frac{\text{workdone}}{\text{time}}\) Dimension of work done ( F x S = M x A x S ) = MLT\(^{-2}\) L = ML\(^2\)T\(^{-2}\) Dimension of time = T Therefore, the dimension of power = \(\frac{ML^2T^{-2}}{T}\) = ML\(^2\)T\(^{-3}\)

A standard vernier caliper usually has the least count (its degree of accuracy) of 0.01 cm, meaning it can make measurements to the nearest hundredth of a centimeter. This level of precision allows for accurate readings in various applications.

A standard meter rule has markings that are usually every millimeter (1 mm). The least count, which is the smallest measurement that can be accurately read, is often 1 mm. The least possible error is generally considered to be half of the smallest division, so it is \pm0.05cm (or \pm0.5mm).

The activation energy is the energy required to get the reaction going. It's the difference between the energy of the reactants and the peak of the hump.

The effect of pressure on a chemical system at equilibrium is only on gaseous substances. We'll need to consider the number of moles of the gaseous substances on the LHS as well as the total number of moles of the gaseous substances on the RHS. The side with the lower total number of moles will be favoured by an increase in pressure and vice versa. However, since the number of moles of the gaseous substances on both sides are 1, i.e they are equal, an increase in pressure has no effect on the chemical system in equilibrium.

Mechanical advantage of a machine = \(\frac{\text{LOAD}}{\text{EFFORT}}\) In this case of a wedge, we can consider the dimensions given: Load distance (height of the machine): 15 cm Effort distance (movement of the effort): 0.5 cm M.A = \(\frac{15}{0.5}\) = 30.0