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When two vectors are perpendicular, the angle between them is 90 degrees, resulting in the component of one vector along the direction of the other being zero.

Energy density = \(\frac{\text{Energy}}{\text{Volume}}\) = \(\frac{\text{Joule}}{m^3}\) = \(\frac{kg m^2 s^{-2}}{m^3}\) = kgm\(^{-1}\)s\(^{-2}\)

I. Work done by load is always less than the work done by effort. This statement is generally true for all machines because some of the work done by the effort is used to overcome friction and other resistive forces in the machine. III. A fishing rod is a machine. This statement is true as a fishing rod is a simple machine that uses a lever to catch fish.

E = hf f = (E)/h ∴ f = (3.3 x 1.6 x 10-19)/6.6 x 10-34 = 0.8 x 1015 = 8.0 x 1014 Hz

This process occurs when the thermal energy of the metal is sufficient to allow electrons to overcome the work function and escape from the surface.

Forward Biased Definition: A battery connection that allows current to flow across a p-n junction. Positive terminal to the p-type semiconductor and negative terminal to the n-type.Reduces the potential barrier, allowing charge carriers (holes and electrons) to move toward the junction and enabling current flow.

Neutral: Gamma rays are a form of electromagnetic radiation and carry no electric charge. Massive: Gamma rays are mass less photons. Positively/Negatively Charged: They do not have any charge, distinguishing them from particles like protons (positive) or electrons (negative)

Band Theory: This theory describes the energy levels of electrons in solids as bands. It explains how the bands (valence and conduction bands) determine the electrical properties of materials.

I. The number of neutrons released exceeds the number that caused the fission. fission releases additional neutrons that can initiate further reactions. II. There is loss of mass. mass is converted into energy according to Einstein’s equation E = mc\(^2\) III. Energy is produced. significant energy is released during the fission process.

An n- type semi conductor is usually formed by dopping the semi conductor(a four valent element)with a five valent element.(arsenic and antimony)

Rectification: A diode allows current to flow in one direction, making it suitable for converting alternating current (AC) to direct current (DC). Diodes are commonly used in power supplies to rectify AC voltage.

Center of Curvature: For a concave mirror, the center of curvature (C) is located at twice the focal length. With a focal length of 5 cm, C is at 10 cm. Object Placement: The object is placed at 10 cm, which is exactly at the center of curvature. Image Formation: When an object is at the center of curvature, the image is also formed at that same point, resulting in a real and inverted image (When the object is located at the center of curvature, the image will also be located at the center of curvature.)(For concave mirror)

Refraction index (n) = \(\frac{\text{Real depth}}{\text{App. depth}}\) For 80 m Real depth: \(\frac{4}{3}\) = \(\frac{80}{\text{App.depth}}\) App. dept = \(\frac{80 \times 3}{4}\) = 60 m For 60 m real depth; \(\frac{4}{3}\) = \(\frac{60}{\text{App.depth}}\) App. depth = \(\frac{60 \times 3}{4}\) = 45 m ∴change in App. depth = 60 - 45 = 15 m

Non-luminous objects do not emit light; instead, they are visible because they reflect light from luminous sources (such as the sun or artificial lights). This reflection allows us to see them.

In a closed tube, the fundamental note occurs when the length of the tube l = \(\frac{\lambda}{4}\), the first overtone occurs when the length of the tube l = \(\frac{3 \lambda}{4}\) \lambda = \(\frac{4l}{3}\) = \(\frac{ 4 \times 33}{3}\) = 44 cm