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Sound waves are mechanical waves that are longitudinal. This means that the particles of the medium through which sound waves travel, such as air or water, move back and forth in the same direction as the wave travels.

d=312m.,T =263\(-10^^\circc\) = -10+273K = 263K, t=? v= 331\sqrt \(\frac{T}{273}\) ⇒ v = 331\times\sqrt \(\frac{263}{273}\) ⇒ v = 324.88 \(ms^-1\) ⇒ v = \(\frac{d}{t}\) t = \(\frac{d}{t}\) = \(\frac {312}{324.88}\) t = 0.96s

The frequency of a sound wave is proportional to the tension of the string. If two instruments have the same frequency, but one has a tighter string, then the instrument with the tighter string will have a higher pitch. The other factors listed, such as the size of the instrument, the material of the instrument, and the shape of the instrument, will also affect the pitch of the instrument, but they will have a smaller effect than the tension of the string.

T=800N; I=50cm=0.5m, m=10g=0.01kg fundamental freq: \(f_o\) =? \(f_o\) = \(\frac{1}{21}\sqrt{T}{\mu}\) \mu =\(\frac{m}{1}\)=\(\frac{0.01}{0.5}\) ⇒ \(f_o\) =\(\frac{1}{2\times0.5}\)\sqrt\(\frac{800}{0.02}\) \(f_o\) ⇒\sqrt 40,000 ⇒1st overtone = 2\(f_o\) =2\times200 = 400Hz ⇒2nd overtone =3\(f_o\) =3\times200=600Hz ∴3rd over tone= 4\(f_o\) =4\times200=800Hz

Instrument resolution is not a limitation of experimental measurements. It is the smallest change in a measured quantity that can be detected by an instrument. While instrument resolution limits the accuracy of a measurement, it is not a limitation of experimental measurements itself.

Diffraction is the bending of waves around the corners of an obstacle or through an aperture.

The magnitude of the electric field strength at any point between the plates is not directly proportional to the magnitude of the charge on each plate. Instead, it is directly proportional to the charge density (charge per unit area) on the plates. Therefore, if the charge on the plates is increased while keeping the area of the plates constant, the electric field strength will increase. However, if the area of the plates is also increased such that the charge density remains constant, the electric field strength will not change.

Number of cycles, n = \(2\frac{1}{2} = \frac{5}{2}\) Length = n\lambda \lambda = \(\frac{Length}{n}\) = \(\frac{125}{\frac{5}{2}}\) Therefore, \lambda = 50cm = 0.50m.

F = qvB ( force on moving charge in a magnetic field) F = \(\frac{mv^2}{r}\) equating F qvB = \(\frac{mv^2}{r}\) qB = \(\frac{mv}{r}\) qBr = mv Therefore, v = \(\frac{qBr}{m}\)

The pitch of a sound is determined by its frequency. Higher frequencies correspond to higher pitches. For example, a high-pitched sound like a whistle has a higher frequency than a low-pitched sound like a drum.

The expression for the escape velocity \(v_e\) of an object from a planet of mass M and radius R using the universal gravitational constant G is: \(v_e = \frac{\sqrt{2GM}}{R}\)

An atom in an excited state is one whose electrons have moved to a higher energy level. In an atom, electrons are typically found in specific energy levels or orbitals. When an electron absorbs energy, it can move from a lower energy level to a higher energy level, which is referred to as an excited state. In this higher energy state, the electron is farther from the nucleus and has more potential energy. When the electron returns to its lower energy level, it emits the excess energy as electromagnetic radiation, often in the form of visible light. This is what gives rise to the characteristic spectral lines observed in spectroscopy.

V = 220V, P = 1.60KW = 1060W, I = ? P = IV I = \(\frac{P}{V} = \frac{1060}{220}\) ≈ 5A.

v = 120m/s, \lambda = 0.50m, f = ? v = f\lambda f = \(\frac{v}{\lambda} = \frac{120}{0.50}\) Therefore, = 240Hz.

The diagram above is a full wavelength and the length of an open pipe during first overtone equals one wavelength i.e. l = \lambda