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The metal blade transfers heat away from your skin more effectively than the wooden handle. When you touch the blade, it rapidly absorbs heat from your hand, causing it to feel colder. In contrast, the wooden handle, which is a less effective conductor of heat, doesn't draw heat away as quickly, making it feel warmer in comparison.

Identical (I): The waves should have the same frequency and wavelength. Coherent (III): The waves must maintain a constant phase relationship. Monochromatic (IV): The waves should have the same frequency (which is closely related to being coherent).

In a large auditorium perforated, absorbent materials are used to line the ceiling so as to reduce the effect of multiple reflection of echo called reverberation

The phenomenon of light bending around an obstacle is: diffraction

Kaleidoscope is an optical instrument that creates patterns and designs by reflecting light through coloured materials.

N = 1.5 = \(\frac{(speed of light in glass)}{\text{speed of light in air}}\) \(\frac{1.5}{1}\) = \(\frac{(3.0 \times 10^8)}{\text{V}}\) V = \(\frac{(3.0 \times 10^8)}{1.5}\) V = 2.0 x 10\(^8\) ms\(^{-1}\) But x = Vt t = \(\frac{\text{x}}{\text{Vt}}\) t = (x)/v = \( \frac{9 x 10^{-3}}{2.0 x 10^8}\) ∴ Time = 4.5 x 10\(^{-11}\)S

Simple microscope: A single convex lens used to magnify small objects. It allows the viewer to see details that are not visible to the naked eye.

A pure spectrum can be produced using a triangular prism-two converging lenses and a narrow slit of white light

In general, electric field strength E = \(\frac{(F)}{q}\) E = \(\frac{q}{4\pi\varepsilon_0d^2}\) ⇒ 360 = \(\frac{9\times10^9\times50\times10^-6}{d^2}\) solving, we have \(d^2\) = 1250 putting \(d^2\) = 1250 into the second equation, E = \(\frac{9\times10^9\times120\times10^-6}{1250}\) we have E = \(864NC^-1\)

E = HF = (hc)/\lambda E\lambda = hc ∴ X = hc ==6.63 x 10\(^{-34}\) x 10\(^8\) = 1.989 x 10\(^{-25}\) =1.99 x 10\(^{-25}\)

Semiconductors, such as silicon and germanium, primarily exhibit covalent bonding, where atoms share electrons to form a stable structure.

Aluminum has three valence electrons, while silicon has four. When aluminum is added to silicon, it creates "holes" (positive charge carriers) because there is one less electron to form a bond. These holes can move and carry charge, making the material p-type. Charge Carriers: Majority carriers in p-type semiconductors are holes. While, Arsenic (or other elements When doped into germanium (which has four valence electrons), the extra electron becomes free to move, which increases the number of negative charge carriers (electrons) in the material. This results in an n-type semiconductor. Charge Carriers: Majority carriers in n-type semiconductors are electrons

\(\lambda\) = \(\frac{h}{mv}\), then, h = mv\(\lambda\) m = \(\frac{h}{v \lambda}\) = \(\frac{6.63 \times 10^{-34}}{6.0 \times 10^{-7} \times 3 \times 10^8}\) = 3.68 x 10\(^{-36}\) kg OPtion A is the closest.

Resolution of force: Total vertical upward force: = 3√3 + 10 cos 60o = 3√3 + 5. Total downward force = 6 cos 30o = 6 x √(3/2) = 3√3 Total horizontal forces towards right; = 3N + cos 30o = 3N + 10 x √(3/2) = 3N + 5√3 Total horizontal forces towards left: = 6 cos 60o = 6 x 0.5 = 3.0N Summary: Vertical resultant forces upward: = 3√3 + 5 - 3√3 = 5N Horizontal resultant forces towards right: = 3N + 5√3 - 3√3 = 5N Horizontal resultant force towards right = 3N + 5√3 - 3N = 5√3N ∴ R2 = 52 + (5√3)2 = 25 + 25 x 3 = 100 ∴ R = √100 = 10N

The ball has its fastest speed at its equilibrium position when its displacement X = 0, which is at X. At this point, the bob has maximum velocity and maximum kinetic energy.