JAMB UTME - Physics - 2011

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

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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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Resistance in metals are proportional to temperature

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

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

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

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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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Steel is not easily magnetized and dismagnetized

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

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grease is more viscous than the rest of the liquids

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

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

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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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presbyopia is loss of accommodation

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

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

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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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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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Dull, black surface are good emitters or absorbers of energy

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

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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