Capacitance C is defined as C = Q/V. If C is doubled and Q remains constant, then V must halve to maintain the equation.

The capacitance C of a parallel plate capacitor is given by C = εA/d. If the distance d is doubled, the new capacitance will be C/2.

Capacitance C = Q/V. If Q is doubled and V remains constant, C must also double.

The electric field E between the plates of a capacitor is directly proportional to the charge. If the charge is doubled, the electric field also doubles.

Using Ohm's Law, R = V / I = 6V / 2A = 3Ω.

Using Ohm's Law, R = V / I = 9V / 3A = 3Ω.

The heat produced is proportional to the square of the current (H ∝ I²), so if I is doubled, heat becomes 4 times.

Using Ohm's Law, V = I * R = 5A * 10Ω = 50V.

Tensile strength is inversely proportional to the cross-sectional area. Halving the diameter reduces the area to a quarter, thus tensile strength quadruples.

If the distance d is halved, the capacitance C = εA/d will double.

According to the inverse square law, if the distance is doubled, the force becomes 1/(2^2) = 1/4 of the original force.

According to Coulomb's law, the force F is inversely proportional to the square of the distance (F ∝ 1/r^2). If r is tripled, F becomes 1/9 of its original value.

Increasing the distance from the slits to the screen increases the fringe width, as fringe width β is proportional to the distance.

The potential difference (V) between the plates is given by V = Ed, where E is the electric field and d is the distance between the plates.

For the reverse reaction, Kc is the reciprocal of the forward reaction. Therefore, Kc (reverse) = 1/Kc (forward) = 1/10 = 0.1.

ΔTf = Kf * m; -5 = -1.86 * m; m = 5 / 1.86 = 2.68 m.

Freezing point depression = i * Kf * m = 2 * 1.86 °C kg/mol * 1 mol/kg = 3.72 °C. Thus, freezing point = 0 - 3.72 = -3.72 °C.

The period T is inversely proportional to frequency f. If f is doubled, T is halved.

The time period (T) is the reciprocal of frequency (f). Therefore, T = 1/f = 1/50 Hz = 0.02 s.

Inductive reactance (X_L) is directly proportional to frequency (f). Therefore, if frequency increases, X_L decreases.

Inductive reactance (X_L) is given by X_L = 2πfL. If the inductance (L) is doubled, X_L will also double.

Resistance (R) is directly proportional to length (L). If length is doubled, resistance also doubles.

Average induced emf = -ΔΦ/Δt = -(0.2 - 0.5)/2 = 0.15 V = 150 V.

An induced EMF is generated when there is a change in magnetic flux through a coil.

If the mass of the Earth doubles, the acceleration due to gravity also doubles, as it is directly proportional to mass.

The energy stored in a capacitor is given by U = 1/2 CV^2. If V is halved, the energy becomes U' = 1/2 C(V/2)^2 = 1/8 CV^2, which is halved.

The charge (Q) stored in a capacitor is directly proportional to the potential difference (V) across it, given by Q = CV.

Work done (W) = Charge (Q) × Potential difference (V) = 2 C × 10 V = 20 J.

The focal length (f) of a concave mirror is given by f = R/2, where R is the radius of curvature. Thus, f = 20 cm / 2 = 10 cm.

The focal length f of a lens is given by f = R/2. Therefore, f = 20 cm / 2 = 10 cm.