Physics Past Questions and Answers

Write down the name of:<br/>(a) two particles used in explaining the wave nature of matter;<br/>(b) one device whose invention is based on the wave nature of matter.

(a) what is Brownian motion?<br/>(b) State the two inferences that can be drawn from Brownian motion experiment.

(a) State the triangle law of vector addition.<br/>(b) Name the four physical quantities that are associated with the equationq of linear motion.<br/>(c) Using the same set of axes, sketch and label two graphs to illustrate the variation of potential energy and kinetic energy with time for a body in simple harmonic motion.<br/>(d)<br/><br/>A light spiral spring of force constant K lies on a horizontal frictionless surface and has one end fixed to a vertical wall. A block P of mass 2.0 kg placed against the free end of the spring is pushed a distance 5 cm towards the wall with 10J of energy as illustrated in the diagram above. The block is released and after 0.25s, it collides inelastically with a stationary block Q of mass 4.0 kg. Calculate the:<br/>(i) value of k;<br/>(ii) force used to compress the spring;<br/>(iii) acceleration of the block p after release;<br/>(iv) common speed after collision of the blocks.<br/>

(a) On which day would sound wave travel faster: on a hot or cold day? Explain.<br/>(b) Why are megaphones shaped like funnels?<br/>(c) A ray of light is incident on a surface of a ectangular glass prism of refractive index 1.5 illustrated in the diagram below.<br/><br/>(i) Copy the diagram a label the angles of: (\(\alpha\)) Incidence (x); (\(\beta\)) Reflection (y); (\(\gamma\)) refraction (z); with t glass letters indicated.<br/>(ii) Calculate the angle refraction to the nearest whole number.<br/>(d) A sonomesr wire vibrates in simple harmoi motion with a maximum amplitude of 1.0 cm. Calculate the frequency of vibration of the wire, giv that the magnitade of the maximum acceleration of the wire is 980ms\(^{-2}\). [\(\pi \frac{22}{7}\)]

(a) Explain briefly the purpose of earthing electrical appliance.<br/>(b) Why does the light frorr bulb connected to a simple cell dim and eventually goes off after a while?<br/>(c) A coil of incidence 0.007 H, a resistor of resistance 8 \(\Omega\) and a capacitor capacitance 0.001 F are connected in series an a.c. source of frequency \(\frac{500}{\pi}\)Hz. If the r.m.s voltages across the coil, the resistor and capacitor are 30v, 20v and 70v respectively;<br/>(i) draw a vector diagram to illustrate the voltage across the components in the circuit.<br/>(ii) Calculate the: (\(\alpha\)) r.m.s voltage of the source<br/>(\(\beta\)) r.m.s current in the circuit;<br/>(\(\gamma\)) power dissipated in the circuit.<br/>iii) write down the sinusoidal equation for the r.m.s voltage, V, in terms of the time, t.