JAMB UTME - Physics - 1999
Vraag 1 Verslag
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Vraag 2 Verslag
In fleming's right-hand rule, the thumb, the forefinger and the middle finger if held mutually at right angles represent respectively, the
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Vraag 3 Verslag
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Vraag 4 Verslag
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Vraag 5 Verslag
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Vraag 6 Verslag
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This energy is converted to heat energy - mcΔt
∴ From the principle of energy conversion,
mcΔt = mgh
m x 450 x Δt = m x 10 x 20
∴ Δt = m x 10 x 20/(m x 450)
= 200/450
= 4/9°C
Vraag 7 Verslag
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Energy before hitting ground is = P.E at the height of 15m.
P.E = mgh = 0.1 x 10 x 15 = 15 J
Vraag 8 Verslag
In the J-tube above, Y and X are on the same horizontal level and 30cm3 of air is trapped above Y when the atmospheric pressure is 75cm Hg, calculate the volume of air trapped above Y when 15cm Hg is now poured into the limb above X
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Vraag 9 Verslag
The figure above represents a frictionless pulley system in which a weight W is in equilibrium with a weight of 40N. Find the value of W.
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Vraag 10 Verslag
The diagram above represents a transverse electromagnetic wave travelling with speed 3.0 x 108ms-1. What is the frequency of the wave.
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Where λ = wavelength
From the above, the distance OA = one wavelength; AB = one wave length and BC = one wavelength.
=> OC = 3 wavelength = 3λ
∴3λ = 0.3M
λ = 0.3/3
= 0.1m
∴ f = V/λ = (3.0 x 108) / 0.1
= 3.0 x 109Hz
Vraag 11 Verslag
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= 80−200.02
= 600.02
= 3000Km-1
= 3.0 x 103Km-1
Vraag 12 Verslag
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Vraag 13 Verslag
The diagram above shows a magnet X with its south pole moved along a soft - iron bar PQ in the direction shown. After some time, the poles at P and Q respectively are
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Vraag 14 Verslag
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Vraag 15 Verslag
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Let P1 = P0 and V1 = V0, then solve accordingly.
Vraag 16 Verslag
The diagram above shows a lift pump with valves at P and Q. During a downward stroke of the piston
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Vraag 17 Verslag
The diagram above shows the velocity-time graph of a vehicle. Its acceleration and retardation respectively are
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∴ acceleration and retardation = 4m/s2; 2m/s2
Vraag 18 Verslag
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Vraag 19 Verslag
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Vraag 20 Verslag
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Vraag 21 Verslag
In the circuit above, The potential across each capacitor is 100V. The total energy stored in the two capacitors is
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Vraag 22 Verslag
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Vraag 23 Verslag
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Vraag 24 Verslag
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Vraag 25 Verslag
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E = hf = hV/λ (since V = fxλ)
But in terms of mass M, E = ∆MV2
∴ ∆MV2 = hV/λ
∆MV = h/λ
∴ V = h/λ∆M
V = 6.63 x 10-34/(10-27 x 10-8)
V = 6.63 x 10-34/10-35
V = 6.63 x 10-34+35
V = 6.63 x 10
V = 66.3ms-1
Vraag 26 Verslag
The diagram above shows a solid figure with base PQ and center of gravity G on a inclined plane. Which of the following statements is correct
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Vraag 27 Verslag
Calculate the mass of ice that would melt when 2kg of copper is quickly transferred from boiling water to a block of ice without heat loss;
Specific heat capacity of copper = 400JKg-1K-1
Latent heat of fusion of ice = 3.3 x 105JKg-1
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Vraag 28 Verslag
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Vraag 29 Verslag
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(0.05 x 200) - (0.95 x 0) = (0.05 + 0.95) x V (since collision is inelastic).
Thus V = 10m/s.
K.E = 1/2 (0.05 + 0.95) x 102
K.E = 1/2 (1 x 100) = 50 J
Vraag 30 Verslag
In the diagram above, if the internal resistance of the cell is zero, the ration of the powers P1 and P2 dissipated by R1 and R2
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Vraag 31 Verslag
In the circuit above, the ammeter reads a current of 5.0 A when R = 8? and reads 7.0A when R = 5?. The value of the unknown resistance X is
Vraag 32 Verslag
2311Na + Proton → pqX + alpha particle
What are the values of p and q respectively in the equation above?
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Represent;
2311Na + 11P → pqX + 42He
Thus from the above equations, p = 20 and q = 10
Vraag 33 Verslag
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Vraag 34 Verslag
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Vraag 35 Verslag
A solid weigh 10 .00 N in air, 6 N when fully immersed in water and 7 . 0 N when fully immersed in a liquid X. Calculate the relative density of the liquid, X.
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R.D = loss in weight in liquid X loss in weight in water.
R.D = (10 - 7)/(10 - 6) = 3/4
Vraag 36 Verslag
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800(25−0)20×25 = 2.5 x 10 4 watts
Vraag 37 Verslag
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Strain = e/l0. = (10.05 - 10.00)/10.00 = 0.005
Thus Y = 107/0.005 = 2 . 0 x 109Nm-2
Vraag 38 Verslag
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However, the effective internal resistance adds as parallel arrangement given as
1/r = 1/r1 + 1/r2 + 1/r3 + 1/r4
= 1/4 + 1/4 + 1/4 + 1/4
= 1Ω
∴ r = 1Ω
Answer = 1.5V, 1Ω
Vraag 39 Verslag
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R = igrg/(I - ig)
Where R = 0.05Ω
rg = 5Ω
I = 2M
∴ ig = IR/(rg + R)
= (2 x 0.05)/(5 + 0.05)
= 0.10/5.05
= 0.0198A
= 19.8mA
= 20mA
Vraag 40 Verslag
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Vraag 41 Verslag
I. A liquid boils when its saturated vapour pressure is equal to the external pressure
II. Dissolved substances in pure water lead to increase in the boiling point.
III. When the external pressure is increased, the boiling point increases.
IV. Dissolved substances in pure water decrease the boiling point.Which combination of the above are peculiarities of the boiling point of a liquid?
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Vraag 42 Verslag
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Vraag 43 Verslag
The equation of a wave travelling along the positive x-direction is given by;
Y = 0.25 x 10-3 sin (500t - 0.025x).
Determine the angular frequency of the wave motion.
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Vraag 44 Verslag
A 3000W electric cooker is to be used on a 200V mains circuit. Which of the fuses below can be used safely with the cooker?
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The maximum current drawn by the cooker is given by;
I = P/V
∴ I = 3000/200
I = 15A
Thus the most suitable fuse to be used is a 10A fuse
Vraag 46 Verslag
In the series a.c circuit shown above, the p.d across the inductor is 8Vr.m.s and that across the resistor is 6Vr.m.s. The effective voltage is
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Vraag 47 Verslag
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Vraag 48 Verslag
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Vraag 49 Verslag
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Vraag 50 Verslag
