1 ai )
i )Rockets are used for space travels .
ii )Rockets are used for launching satellites into space
1 aii )
i )Artificial Satellites are used to send signals for
televisions , radio , etc
ii )Artificial satellites they are used for monitoring cloud
patterns for a weather station
1 b )
A propeller like piece called turbine is been rotated
continuously by falling water from a dam, which then
turns a metal shaft in an electric generator , which is the
motor that produces electricity
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2 a )
i )distance covered = 5 m +10 m = 15 m
ii )magnitude of his displacement
= a ^ 2 = b^ 2 +c ^ 2
x ^ 2= 5 ^ 2 + 10 ^ 2= 25 + 100
x ^ 2= 125
x = sqr 125
= 5 sqr 5 m
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4 a )
i )pulley
ii )the inclined plane
4 b )
CLICK HERE TO VIEW THE IMAGE
load - - - - - - > fulcrum - - - - - - > effort
eg - crowbar
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5 )
V 1 =700cm ^ 3, T 1 =30 dgree- census + 273=303k ,
P 1 =606mmHg
V 2 =700- 300= 400cm^ 3 , T 2 =47 +273= 320k
from general gas law
P 1 V 1/ T 1 = P2 V 2 /T 2
606* 700/303= P 2 * 400/ 320
P 2 =606* 700* 320/303* 400
P 2 =1120 mmHg
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8 a )
Electric current is the rate of charge flow past a given
point in an electric circuit , measured in Coulombs /second
which is named Amperes .
8 b )
d = 30 cm , £ =1 . 5* 10 ^ - 5 c r = 30 cm
30 /100= 0 . 3 m
V = kE/ r = 9* 10 ^ 9 * 1 . 5 * 10 ^ - 5 /0 . 3
= 13 . 5* 10 ^ 4
= 13 . 5* 10 ^ 5 /3
V = 4. 5 * 10 ^ 5
V = 450kv
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9 a )
i )by heating
ii )electrical method
9 b )
energy stored =1 / 2CV ^ 2
given that t
C = 4HF = 4 * 10 ^ - 6F
v = 800v
= 1 /2 * 4 * 10 ^ - 6 * 800* 800
= 2 * 800* 800* 10 ^ - 6
= 1280000 j * 10 ^ - 6
= 1 . 28 j
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11 )
Tabulate
- Hard Xray-
i )high penetrating power
ii )short wave length
iii ) produce high voltage
- soft Xray -
i )low penetrating power
ii )long wave length
iii ) produced at low voltage
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( 12 a )
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centre of gravity can be define as the point through which
the line of action of the weight of the body always passes
irrespective of the position of the body .Naijacomms.com
12 b)
C . g = centre of gravity
: - v = u - gt
Of maximum height v = O - K
O = u - gt
For vertical component, U = uSin tita
Therefore O = usin tita - gt
gt =uSin tita
T = uSin tita / g
Where T is the time taken to maximum height
12 c )Naijacomms.com
Taken moment about point A
Cwm = { 60 * 10 ) + (20 * 60 )
Cwm = 600+1200
Cwm = 1800
Acwm = (20 * 40 ) + ( R 3 * 40 )
Acwm =800+ 80 R 3
At equilibrium , Cwm = Acwm
1800 = 800+40 r 3
1800 - 800= 40 r 3
1000 = 40 r 3
R 3 =1000 / 40
R 3 =25 N
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13 a)
dew point is the temperature at which the water vapour
present in the atmosphere is just sufficent to saturate it
13 b)
mist is formed as a result of condensed drops of
moisture throughout the mass of cooled air . That is
when water droplet in the air cool suddenly
13 ci )
the plastic comb will acquire electric charges
13 cii)Naijacomms.com
the plasic com can attract small pieces of paper due to
the acquired charges
13 di )
area expansivity (B )= 2 §
= 2 * 1 . 2 * 10 ^ - 5
B = 2. 4 * 10 ^ - 5 1k
13 dii )
given that initial length= 6 cm
initial area A = 6* 6 =36 cm^ 2
rise in temperature =25 k
linear expansivity =1 . 2 * 10 ^ - 5 /k
area expansivity = 2 . 4 * 10 ^ - 5 /k
new area At =Ao (1 + Btita)
At = 36 (1 +2 . 4 * 10 ^ - 5 * 25 )
At = 36 (1 + 60 * 10 ^ - 5 )
At = 36 (1 +0 . 0006 )
At = 36 (1 . 0006 )
At = 36 . 0216
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15 a)
electrical potential is the workdone in driving a unit
charge of electric current from one point to another in aNaijacomms.com
closed circuit. It is measured in volta ( V)
15 b)
DIAGRAM LINK COMMING SOON
A metal rod can be made into a magnet by divided touch
me thod as shown in the diagram above .Naijacomms.com
The metal rod is stroke at the middle with opposite pole
end of two permanent magnets towards the opposite
ends several times opposite polarity are then formed
15 ci )
DIAGRAM LINK COMMING SOON
VR = 120v - - - - > Vl =50 v - - - - > Vc= 134. 39 v
220v , 506z
15 cii)Naijacomms.com
V ^ 2= Vr^ 2 +( Vl - Vc )^ 2
220^ 2 =120^ 2 +( 50 - Vc )^ 2
48400 =14400 +( 50 - Vc)^ 2
48400 =14400 =( 50 - Vc)^ 2
34000 =( 50 - Vc)^ 2
50 - Vc= sqr 34000
50 - Vc= 184. 39
- Vc= 184. 39 - 50
Vc =134. 39 v
; the potential difference acrross the capaitor is 134. 39 v
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