2017 WAEC PHYSICS ANSWER

2017 WAEC PHYSICS ANSWER loading.. .  [8:53AM,  8b)

If their distance and masses are doubled their corresponding force would also be doubled and the work done respectively

I.e.Workdone=Force * distance

Force= Mass * Acceleration

W= Mg * d

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Increase

8c)

-Acceleration due to gravity

- At maximum height, final velocity is zero

8d)

i)pushing someone on a swing.

ii)Tuning a radio to a particular frequency.

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10a)

A wave front is an imaginary surface passing through the points of a medium oscillatory in phase

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[9:29AM, 4/10/2017] Lijoka CTE: SECTION A ANS 5QUESTION

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1)

decrease in height (h)

increase in time (t)

this shows that distance changes with time

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3)

i)Brownian motion

ii)Atomic size

iii)Expansion

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2)

given that U=15m3^-1

R=U* sqr2h/g

h=20m

g=10

R=15*sqr2*20/10

R=15*sqr40/10

R=15*sqr4

R=15*2=30m

R=30m

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4)

L1=14cm F1=4N,F2=6N

L2=4cm, Lo=?

Using hooke’s law

4/14-Lo*6/4-Lo

4(4-Lo)=6(14-Lo)

16-4Lo=64-6Lo

-4Lo+6Lo=64-16

2Lo=48

Lo=48/2

Lo=24Cm

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5a)

i)force

ii)length

5b)

by increasing the density mosquitoes lavrva

than the density of water

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6)

A)Energy efficient- so far the best light for

interior lighting

B)Low production cost (of tubes, not of the

ballasts)

C)Long life of tubes

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7)

i)It requires low voltage sources for it to

function

ii)It cannot be easily broken

iii)It is cheaper and quite easy to

manufacture

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8b)

If their distance and masses are doubled

their corresponding force would also be

doubled and the work done respectively

I.e.Workdone=Force * distance

Force= Mass * Acceleration

W= Mg * d

|

Increase

8c)

-Acceleration due to gravity

– At maximum height, final velocity is zero

8d)

i)pushing someone on a swing.

ii)Tuning a radio to a particular frequency.

================================

===

10a)

A wave front is an imaginary surface passing

through the points of a medium oscillatory in

phase

8c) -Acceleration due to gravity

– At maximum height, final velocity is zero

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SECTION B ANS 3 QUESION

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12ai)

Nuclear fission is a nuclear reaction in which

a heavy nucleus splits spontaneously or on

impact with another particle, with the release

of energy.

12aii)

A graphite reactor is a nuclear reactor that

uses carbon as a neutron moderator, which

allows un-enriched uranium to be used as

nuclear fuel.

12aiii)

Boron rods are used in

nuclear reactors to control the fission rate of

uranium and plutonium. They are composed

of chemical elements such as boron, silver,

indium and cadmium that are capable of

absorbing many neutrons without themselves

fissioning.

[9:36AM, 4/10/2017] Lijoka CTE: obj

1-10 caabadaccc

11-20 baaddcbada

21-30ccba--cbab

31-40-caddbbbac

41-50 bcda--abca

[10:21AM, 4/10/2017] Lijoka CTE: U gat to wait for the remaining one pls

[10:54AM, 4/10/2017] Lijoka CTE: 11aii) GIVEN: A = 9.6 * 10^-3 M^2

d = 2.25 * 10^4

Eo = 8.85 * 10^-12 F/m

Er = 900

C = /

using; C = EoErA/d

capacity, C = 8.85*10^-12 * 900 * 9.6*10^-3/2.25 * 106-4

C = 33984 * 10^-11

C = 3.3984 8 10^7 F

C =0.344F

11bi) A voltmeter has a higher resistance because it is designed to limit the flow of current to practically zero to avoid voltage drop or less across it.

11bii) combined resistance Rt

Rt = (400 * 400/400 + 400) + (800 * 800/800+ 800)

Rt = 200 + 400

Rt = 600ohms

current supplied by battery = r/Rt

= 6/600

= 0.01A

voltage drop across the resistance = 200 * 0.01

=2V

therefore the voltage reading is 6 -2 

= 4V

11c) Equivalent resistance is:

Rt = 2+2+(2*2/2+2)

Rt = 4+1 

Rt = 5ohms