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\(\frac{1}{3}\)(5 - 3x) < \(\frac{2}{5}\)(3 - 7x) 5(5 - 3x) < 6(3 - 7x) 25 - 15x < 18 - 42x - 15x + 42x < 18 - 25 \(\frac{27x}{27}\) < \(\frac{-7}{27}\) x < \(\frac{-7}{27}\)

The point of intersection are (2.0, 9.0) and (-1.5, 2.0)

If x = -2.5 y = 8.5

Given (-2, 0) ans (0, -4). Gradient = \(\frac{y_2 - y_1}{x_2 - x_1}\) = \(\frac{-4 - 0}{0 - (-2)}\) = \(\frac{-4}{2}\) = -2

x→y means "if x is true, then y is true." The contrapositive of x→y is \simy → \simx, which is logically equivalent to the original implication.

GIVEN DATA: where \DeltaL is the increase in length = 0.01 L1 is the initial length = 100 T1 = 20 T2 = ? \alpha is the linear expansivity of iron = 1.2 x 10\(^{-5}\)^\circC Formula \DeltaL = L1\alpha\DeltaT \DeltaT = \(\frac{\DeltaL}{L1\alpha}\) \DeltaT is the change in temperature = T2 - T1 T2 = \(\frac{\DeltaL}{L1\alpha}\) + T1 T2 = \(\frac{0.01}{100 \times 1.2 x 10^{-5}}\) + 20 T2 = 8.3 + 20 T2 = 28.3

A single pulley is a device composed of a wheel on an axle over which a rope, cord, or similar implement is looped.

Atmospheric pressure equivalence of 10m of water : \(\frac{p_2+10}{p_1+10}\) = \(\frac{40+10}{20+10\) = \(\frac{50}{30}\) = 1.67

The cup containing water at 45∘C loses heat to the room since temperature of the room is lower than its temperature, hence its temperature reduces gradually, the cup containing water at 5∘C gains heat from the room since its temperature is lower than that of the room. hence, its temperature increases gradually, the lines are curved because as the temperature of the water changes the temperature difference between the water and surroundings also changes

In a step down transformer, there are more turns in the primary coil than in the secondary coil and more current flows in the secondary circuit than in the primary.

The V-I graph of an ohmic material is a straight line passing through the origin.

The impedance of a R-L circuit is given by: Z = \sqrt(R\(^2\) + XL\(^2\)) ----------- eqn(1) where Z is the impedance, R is the resistance, and XL is the inductive reactance XL = 2\pifL ------------ eqn(2) where f is the frequency From eqn(2), XL = 2 * \pi * 60 * 0.5 = 60\pi Also, from eqn(1), Z = \sqrt(50\(^2\) + (60\pi)\(^2\)) Z = 195.0\Omega

A real image is defined as An image that is formed when the light rays from an object converge and meet each other and can be projected onto a screen. Real images are always inverted, Real images can be projected onto pieces of paper or screens. An example of a real image is the image formed on a cinema screen. A virtual image is defined as An image that is formed when the light rays from an object do not meet but appear to meet behind the lens and cannot be projected onto a screen. Virtual images are always upright, Virtual images cannot be projected onto a piece of paper or a screen. An example of a virtual image is a person's reflection in a mirror.

The angle of incidence l = 30º The angle of refraction , r =? The refractive index of glass ng = 1.5 The refractive index of ethyl alcohol, ne = 1.36 from snell's law : \(\frac{n_e}{n_g} = \frac{sini}{sinr}\) \(\frac{1.36}{1.5} = \frac{sin30º}{sinr}\) 1.36sinr = 1.5 x sin30º sinr = \(\frac{1.5 \times sin30º}{1.36}\) sinr = 0.5515 r = \(sin^{-1}\)(0.5515) r = 33.5º

The Doppler effect or Doppler shift is the change in frequency of a wave in relation to an observer who is moving relative to the wave source. The drop in pitch of ambulance sirens as they pass by and the shift in red light are common examples of the Doppler Effect.