JAMB UTME - Physics - 2011

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Dielectric constant = (c)/c° = (60)/20 = 3

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Young modules = $\frac{\text{Tensile stress}}{\text{Tensile strain}}$

= $1.1\times {10}^{1}1=\frac{7.7\times {10}^7}{\text{Tensile Strain}}$

∴ Tensile strain = $\frac{7.7\times {10}^7}{1.1\times {10}^{1}1}$

= $7.0\times {10}^{7-11}=7.0\times {10}^{-4}$

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The colour which an object presents to the eye is the colour of light it reflects. Red rose flower will therefore absorb any other colour and reflect red. Therefore when viewed in blue light, it has no colur to reflect and will therefore appear black. Although mixture of red light and blue light = magenta . NO correct option.

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increase in volume, DV = RV1 ∆ θ = 3α Vsub>1 Dθ
= 3 x 2.0 X 10-5 x 40 x (90 - 30)
= 6 x 10-5 x 40 x 60
0.144 cm3
∴ No correct option

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Hot wire ammeter is used because the heat affect of A C is same as that of DC

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The specific latent heat of vaporization of steam is 2.1 x 106JKg-1
while the energy required to raise the temperature of a unit mass of water from 0°c to 100°c = C x Dt = 4200 x 100 = 420000 = 4.2 x 105 JKg-1
? steam possesses greater heat energy per unit mass

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Regelation means refreezing a phenomenon whereby melted ice free from increased pressure refreezed when they are released from the pressure.

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Sound is the only mechanical wave among the rest which are electromagnetic waves.

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Energy consumed = power x time = lvt = 2 x 250 x 6hr = 300 wh = 3 kwh but 1 kwh = N4
3 kwh = 3 x N4 = N 12

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Heat supplied = Heat gained
P x t = C ∆ Ø
(25 x 5 x 60)/300 = 750 JK-1

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grease is more viscous than the rest of the liquids

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Work function, w = hfo 6.6 x 10-34 x 1.3 x 1015
= 8.58 x 10-19

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V = (2X)/t
330 = (2 x 4.95 x 103)/t
t = (9.9. x 103/330 = (9900)/330 = (90)/3
= 30 secs

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S = (1)/2gt2
S = (1)/2 x (10)/1 x 32 =5 x 9 = 45 m

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Under neutral equilibrium, the body rolls and the position of the center of gravity , C. G is neither raised nor lowered

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f1 = 255Hz, T1 = 225N
f2 = ? T2 = 324N
But f ∝ √T => f = K√T
=> K = f/√T
∴ f1/√T1 = f2/√T2225/√225 = f2/√324

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The liquid will rise up the capillary if it wets glass and falls below its wets glass and falls below its initial level if it does not wet glass

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The resultant force acting on the man is given by w = mg - R
Mg - mg = 0
The man feels weightless because the reaction, R is equal to the weight mg

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Resistance in metals are proportional to temperature

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r - rays has the highest frequency followed by X - rays, ultraviolet ray, visible light intra - red and the least is radio weaves

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Effective inductance
(1)/L = (1)/4 + (1)/8 = (3)/8
∴ L = (8)/3
Energy stored = (1)/2 LI2
= (1)/2 x (8)/3 x 10 x 10 = (400)/3 = 133.3 J

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presbyopia is loss of accommodation

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upthrust = weight in air - weight in liquid = 30 x 10 - 22 x 10 = 300 - 220 = 80 N

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The voltage of a circuit is the same whether in parallel or in series. Parallel and series affects resistance and current. So the answer should be it uses less current.

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Pressure in liquid is independent of cross sectional area of the container/ liquid
∴ the correct options are I & II

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Steel is not easily magnetized and dismagnetized

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Efficiency = $\frac{\text{work output}}{\text{work input}}\times \frac{100}{1}$

= 40 = $\frac{20\times 10}{x}\times \frac{100}{1}$
= 500J

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Metals and hydrogen are deposited at the cathode, while non-metals and oxygen are deposited on the anode
∴ metals Y will form the anode which is deposited at the cathode made of x

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m = v/u = -3
v = -3u
f = 15cm
1/v + 1/U = 1/f1/-3U + 1/u = 1/152/3u = 1/15
3U = 15 x 2
U = 30/3
= 10 cm

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v2 = U2 - 2G s
0 = 1002 - 2 x 10 x s = 10000 - 20s
s = (10000)/20 = 500m
Which is independent of mass.the two bodies where acted upon by the same retarding force of gravity which is independent of mass of the body; therefore both will be 500 m from the point of throw.

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K e just before hitting the gound
= P e at the maximum height (conservation of mechanical energy)
K e = P e = mgh = 1.5 x 10 x 20
= 300 J

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Dull, black surface are good emitters or absorbers of energy

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Centripetal force,
F = $\frac{m{v}^2}{r}$
= $\frac{2\times {10}^2}{4}$
= $\frac{200}{4}$= 50N

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Eclipse of the sun occurs when the moon which is opaque objects between the sun and the earth

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Electric potential is work done in taking a unit mass or charge from infinity to that point

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A good thermometric liquid should not have a high thermal capacity so that the themperetue of the body being measured will not be affected
? II, III and IV are qualities of a good thermometer

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T (1)/2 = (0.693)/λ = (0.693)/10-5
= 0.693 x 105
= 6.93 x 104 sec

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The earth radiate heat to the atmosphere at night thereby lowering the temperature of the ground

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V = - 50, U = 25CM
(1)/r = (1)/v + (1)/u = (1)/-50 + (1)/25 = (1 + 2)/50 = (1)/50 f = +50cm = +0.5m
p = (1)/r = (1)/0.5 = (10)/5 = 2 diopters
The power of a lens is the reciprocal of the focal length in meters. it is expressed in diopters.

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Under high potential difference and low pressure gases are good conductor of electricity

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Total energy in parred connection is equal to emt of one cell, = 2v but total internal resistance is given by
(1)/r = (1)/r1 + (1)/r2 + (1)/r3 = (1)/2 + (1)/2 + (1)/2 = (3)/2
∴ r = (2)/3 = 0.67Ω

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The resultant, R is given by pythagoras rule, R2 = P2 + Q2
= 62 + 82 = 36 + 64 = 100
R = √100 = 10.0N