Electrical Resistor Simulator: GCSE, IGCSE & A Level: interactive practice

The following simulator helps you understand and master the calculations involving the resistors, combined both in parallel and series, in circuits. Resistors in Series When resistors are connected in series: The current through them is the same Total resistance is the sum of individual resistance of e…

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Practice Paper for Electric Fields: A - Level Physics

A Level Physics Electric Fields - practice paper Mass of electron: 9 x 10 -31 kg | Charge of electron: 1.6 x 10 -19 Mass of proton: 1.7 x 10 -27 |  Permittivity of air: 8.854 x 10 -12 State Coulomb’ Law. Sketch a graph of the force against the reciprocal of the square of the distance between the two charges…

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Iteration for A Level Maths: staircase method & cobweb method

E.g. f(x) = x² - x - 4 When the above is rearranged in the form of x = g(x), it is said to be in iterative form. x² - x - 4 = 0 x = 1 + x/4 x n+1 = 1 + x n / 4 If x n is known, x n+1 can be calculated. The initial value to trigger off the iterative process is found by looking for change in sign of…

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Simple Harmonic Motion for A Level Physics: vertical motion of a spring

Upward force, T', when the stretched spring is released = k(e+x) If the resultant force is F, F = K(e+x) -mg F = ma - Newton's Second Law k(e+x) - mg = ma, where a is the acceleration (ke + kx) - mg = ma Since T = ke mg - mg + kx = ma ma = kx a = k/m x a ∝ x ω 2  = k/m T =2π √(m/k) T =2π √(m/k) Since the a…

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Mechanics - A Level Applied Maths & Physics: really challenging questions

An object that falls off a tree travels 16/25 th of the height of the tree during the last second. Assuming that g = 10 m/s², find the total time taken for the fall and the height of the tree. A balloon is steadily rising at 5 m/s. After 4 seconds of its motion, a nail from the balloon falls off. Sk…

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Simple Harmonic Motion for A Level Physics: proof of motion of simple pendulum being SHM

As you can see, when the weight of the pendulum bob is resolved, the tension of the string,  T , and the  mg cos x  cancel each other out, leaving  mg sin x  as the net force, as shown above. This force is responsible for bringing the bob down in a curved path. Using F = ma for the bob, mg sin x = ma, wher…

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