grade12

In the circuit diagram below, resistor R,with a resistance of 5,6 Ω, is connected,   together with a switch, an ammeter and a high-resistance voltmeter, to a battery with an unknown internal resistance, r. The resistance of the connecting wires and the ammeter may be ignored. The graph below shows the potential difference across the terminals … Read more

7.1 A small sphere, Y, carrying an unknown charge, is suspended at the end of a   light in extensible string which is attached to a fixed point. Another sphere, X, carrying a charge of +6 x10-6 C, on an insulated stand is brought close to sphere Y. Sphere Y experiences an electrostatic force and comes … Read more

The siren of a police car, which is travelling at a constant speed along a straight   horizontal road, emits sound waves of constant frequency. Detector P is placed inside the police car and detector Q is placed next to the road at a certain distance away from the car. The two detectors record the changes … Read more

An object of mass 1,8 kg slides down a rough curved track and passes point A, which  is 1,5 m above the ground, at a speed of 0,95 m·s-1. The object reaches point B at the bottom of the track at a speed of 4 m·s-1. 5.1 Define the term conservative force.          (2) 5.2 … Read more

A bullet moves east at a velocity of 480 m∙s-1. It hits a wooden block that is fixed to the  floor. The bullet takes 0,01 s to move through the stationary block and emerges from the block at a velocity of 80 m∙s-1 east. See the diagram below. Ignore the effects of air resistance. Consider … Read more

Stone A is thrown vertically upwards with a speed of 10 m∙s-1 from the edge of the roof  of a 40 m high building, as shown in the diagram below. Ignore the effects of air friction. Take the ground as reference. 3.1 Define the term free fall.             (2) 3.2 Calculate the maximum HEIGHT ABOVE … Read more

Block P, of mass 2 kg, is connected to block Q, of mass 3 kg, by a light inextensible  string. Both blocks are on a plane inclined at an angle of 30°to the horizontal. Block Q is pulled by a constant force of 40 N at an angle of 25° to the incline. Block P moves … Read more

1.1 Which physical quantity is equal to the rate of change of momentum?      A Mass             B Impulse  C Net force D Acceleration           (2) 1.2 The gravitational acceleration on the surface of a planet of radius R is g.                The gravitational acceleration at a height of 2R above the … Read more