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A dielectric increases capacitance by becoming polarized and reducing the effective electric field between capacitor plates, allowing more charge to be stored.

Heat energy = Elect. energy heat energy= I2RT = 2 X 2 X 50 X 200 = 40000J to convert to kJ, divide J by 1000 hence, \(\frac{40000}{1000}\) = 40kJ

P = \(\frac{V^2}{R}\) = \(\frac{20 \times 20}{100}\) = 4W

No expanded working has been attached for this question yet. The verified answer is Option C.

\(\frac{V_s}{V_p}\) = \(\frac{N_s}{N_p}\) = \(\frac{I_p}{I_s}\) \(\frac{100}{400}\) = \(\frac{V_S}{12}\) V = 3V

Work function = 5 - 2 = 3eV

Capacitors in parallel = 4\(\mu\)f + 2 \(\mu\) f = 6\(\mu\) f Capacitors in series =\(\frac{1}{C_{eff}}\) = \(\frac{1}{C_1} + \frac{1}{C_2} + \frac{1}{C_3} + \frac{1}{C_4}\) \(\frac{1}{C_{eff}}\) = \(\frac{1}{2} + \frac{1}{3} + \frac{1}{6} + \frac{1}{4}\) = \(\frac{6 + 4 + 2 + 3}{12}\) \(\frac{1}{C_{eff}}\) = \(\frac{15}{12}\) C\(_{eff}\) = \(\frac{12}{15}\) = 0.8\(\mu\) f

No expanded working has been attached for this question yet. The verified answer is Option D.

No expanded working has been attached for this question yet. The verified answer is Option B.

The total upward vertical force must balance the downward weight of 20 N. There are two vertical components: 2 \times (T \times sin(30^\circ)) = 20 N Sin(30^\circ) = \(\frac{1}{2}\) = 0.5 So: 2 \times T \times 0.5 = 20 T = 20

M\(_2\)g - M\(_2\)a = M\(_1\)a + M\(_1\)g Sin\(\theta\) (30 x 10) - 30a = 20a + 20 x 10 x Sin 30 300 - 30a = 20a + 100 - 30a - 20a = 100 - 300 - 50a = - 200 a = \(\frac{-200}{-50}\) = 4m/s\(^2\)

Force required to move the object forward = Fcos 60 = 300 x 0.5 = 150N Frictional Force = 100N Total force acting on the object = 150 - 100 = 50N Work Done = Total force x distance = 50 x 4 = 200J.

Diagram above shows a Parallel circuit If one of the parallel path is broken, current will continue to flow in other parts. Voltage is the same across each component of the parallel circuit. The brightness of a light bulb is given by its power. P = I\(^2\)R, and so brightness depends on current and resistance. Hence; the brightness of Y will not be affected except for a variation in resistance property.

No expanded working has been attached for this question yet. The verified answer is Option C.

The underlined word is inconsequential, which means unimportant or having little effect. The sentence suggests that although the rise in the price of petrol appeared insignificant, it actually had the opposite effect—it had a serious impact on the cost of living.