Question Library

(a) When a positively charged conductor is placed near a candle flame, the flame spreads out as shown in the diagram above. Explain this observation. (b) A proton moving with a speed of 5.0 x 10\(^{5}\) ms\(^{-1}\) enters a magnetic field of flux density 0.2 T at an angle of 30^\circ to the field. Calculate the magnitude of the magnetic fcrce exerted on the proton. [Proton charge = 1.6 x 10\(^{-19}\) C] (c) The diagram above illustrates a 9.0 V battery of internal resistance 0.5 \(\Omega\) connected to two resistors of values 2.0 \(\Omega\) and R \(\Omega\). A\(_1\) A\(_2\) and A\(_3\) are ammeters of negligible internal resistances. If Al reads 4.0 A, calculate the: (i) equivalent resistance of the combined resistors 2.0 \(\Omega\) and R \(\Omega\); (ii) currents through A\(_1\) and A\(_3\) ; (iii) value of R.

(a) State three conclusions that can be drawn from Rutherford's experiment on the scattering of alpha particles by a thin metal foil in relation to the structure of the atom The diagram above illustrates th3 energy levels of an electron in an atom. If an excited electron moves from n\(_2\) to n\(_\theta\), calculate the: (i) frequency; (ii) wavelength of the emitted radiation. [ h = 6.6 x 10\(^{-34}\) Js; le V = .6 x 10\(^{-19}\) J; C = 3.0 x 10\(^8\) ms\(^{-1}\)] (c) The following nuclear equations represent two types of radioactivity. \(^{226}_{88}R_a \to ^{222}_{86}R_n + ^a_2a\) (Equation A) \(^{14}_7N + ^4_2a \to ^{17}_8O + ^1_1p\) (Equation B) Identify each type and explain briefly the difference between them

You are provided with a glass block, a plane mirror, and optical pins. Place the glass block on a drawing sheet and trace its outline ABCD as shown in the diagram above. Remove the block, measure, and record the width W of the block. Draw a normal ON to DC at a point about one-quarter the length of DC. Draw a line making an angle i = 10^\circ with the normal. Replace the block on its outline and mount the plane mirror vertically behind the block such that it makes good contact with the face AB. Stick two pins \(P_1\) and \(P_2\) on the line MO. Looking through the face CD, stick two other pins \(P_3\) and \(P_4\) such that they appear to be in a straight line with the images of pins \(P_1\) and \(P_2\) seen through the block. Join \(P_3\) and \(P_4\) with a straight line and extend it to touch the face CD at O. Draw a perpendicular line from the midpoint of OO to meet AB at QD. Draw lines OQ, O'Q, and normal O'N' produced. Measure and record \(\theta\), e and d. Evaluate m = sin e and n = cos(\(\frac{\theta}{2}\)) Repeat the procedure for i = 20^\circ, 30^\circ, 40^\circ and 50^\circ. Tabulate your readings. Plot a graph with m on the vertical axis and n on the horizontal axis. Determine the slope, s, of the graph and evaluate q = 2Ws. State two precautions taken to ensure accurate results. (Attach your traces to your answer booklet.) (b)i. Explain the term refractive index and give a mathematical expression for it in terms of wavelength. ii. State the conditions necessary for total internal reflection to occur for a given pair of media.

An electric lamp marked 240v, 60 W is left to operate for an hour. How much energy is generated by the filament?

A band of 500 rectangular loops of wire of area 20 cm by 20 cm, encloses a region of magnetic field which charges from 1.0T to 0.4T within 5 seconds, calculate the induced e.m.f.

The pressure of two moles of an ideal gas at a temperature of 27 ^\circC and volume 10\(^-2\)m\(^3\) is? [R = 8.313 J mol\(^{-1}\)K\(^{-1}\)]

In a hydraulic press, a force of 40N is applied to the smaller priston of area 10cm2. If the area of the larger piston is 200cm2, calculate the force obtained

A body of volume 0.046m3 is immersed in a liquid of density 980kgm-3 with \(\frac{3}{4}\) of its volume submerged. Calculate the upthrust on the body. [g = 10ms-2]

Which of the following types of types of motion will be produced when a pair of equal and opposite non-collinear parallel forces acts on a body?

A body moving in a circle at constant speed has i. a velocity tangent to the circle ii. a constant kinetic energy iii. an acceleration directed towards the circumference of the circle. Which of the statements above are correct?

The following properties of a solid are measured on earth i. weight ii. specific heat capacity iii. density. Which of the properties will hav a different value if measured in space?

Two forces 6N and 8N, act eastwards and northwards respectively on a body. Calculate the magnitude of their equilibrant

A body of mass 5kg movimg with a velocity of 30ms-1 due east is suddenly hit by another body and changes its velocity to 50ms-1 in the same direction. Calculate the magnitude of the impulse received.

Electric energy is measured in

A stone of mass 0.5kg is dropped from a height of 12m. Calculate its maximum kinetic energy. [g = 10ms-1]