Physics alt practical now posted

[4/4, 9:10 AM] Dito Dito: Phy - Pract - Answers
1 )
Tabulate
s /n = 1 , 2 , 3 , 4 , 5
L ( cm )= 130 , 110 , 90 , 70 , 50
T 1 ( sec)= 45 . 70 , 42 . 00 , 38 . 00 , 33 . 10 , 28 . 70
T = 2 . 29 , 2 . 10 , 1 . 90 , 1 . 66 , 1 , 44
T ^ 2 = 5 . 22 , 4 . 41 , 3 . 61 , 2 . 74 , 2 . 06
L = 100 , 80 , 60 , 40 , 20
1 )
- precautions -
Take Any Two
i ) I avoided conical oscillation
ii ) I avoided drought
iii ) I avoided parallax error in taking reading from the metre rule
iv ) I avoided zero error in taking reading from the stop watch
pls keep calm we will update
the rest soon
============================
3 )
Tabulate
3 )
- precautions -
take any two
i ) I removed key when reading is not taking
ii ) I ensured tight connections at the terminals
iii ) I avoided parallax error when taking reading from the ammeter.
============================
[4/4, 9:11 AM] ‪+234 813 649 3840‬: 1b i.
focal length of an object is 20means that the distancebetween the optical centre  or middle of the lens and its principal  focus is 20cm

1bii.
given that u=x   f=20   v=5

using the mirror formula
1/u   +  1/v  = 1/F

1/x + 1/5 = 1/20

multiply through by the LCM
1/x *5  + 1/5 * 5 = 1/20 * 5

5/x =5/20
5/x =1/4
taking the reciprocal
x/5 =4/1

cross multiply
x * 1 = 5 * 4
x =20
[4/4, 9:11 AM] Dito Dito: 1b i.
focal length of an object is 20means that the distancebetween the optical centre  or middle of the lens and its principal  focus is 20cm

1bii.
given that u=x   f=20   v=5

using the mirror formula
1/u   +  1/v  = 1/F

1/x + 1/5 = 1/20

multiply through by the LCM
1/x *5  + 1/5 * 5 = 1/20 * 5

5/x =5/20
5/x =1/4
taking the reciprocal
x/5 =4/1

cross multiply
x * 1 = 5 * 4
x =20
[4/4, 9:12 AM] Dito Dito: 2aix)
*PRECAUTIONS*
I)  experiment must be carried out in a dark room
II)  lens, screen and object must be in line
[4/4, 9:27 AM] Dito Dito: Phy - Pract - Answers

1axi)
- *Precautions* -
Take Any Two

i ) I avoided conical oscillation
ii) I avoided drought
iii ) I avoided parallax error in taking reading from the metre rule
iv ) I avoided zero error in taking reading from the stop watch

1b i.
focal length of an object is 20means that the distancebetween the optical centre  or middle of the lens and its principal  focus is 20cm

1bii.
given that u=x   f=20   v=5

using the mirror formula
1/u   +  1/v  = 1/F

1/x + 1/5 = 1/20

multiply through by the LCM
1/x *5  + 1/5 * 5 = 1/20 * 5

5/x =5/20
5/x =1/4
taking the reciprocal
x/5 =4/1

cross multiply
x * 1 = 5 * 4
x =20

3aix)
- *precautions*-
take any two
i ) I removed key when reading is not taking
ii) I ensured tight connections at the terminals
iii ) I avoided parallax error when taking reading from the ammeter .

3bii)  I) length
        II) Thickness

More loading...
E
TYPING.....
[4/4, 9:29 AM] Dito Dito: WAEC Physics Practical Answers.
(1)
TABULATE:
i:1,2,3,4,5,
L(cm):80.00,70.00,60.00,50.00,40.00
t1(s):17.87,16.22,16.09,14.08,13.28
t2(2):17.56,16.46,15.09,14.77,13.36
t(s)mean:17.715,16.340,15.590,14.425,13.320
T(t/10)s:1.7715,1.6340,1.5590,1.4425,1.3320
LogT(s):0.2483,0.2133,0.1928,0.1591,0.1212
Log L(cm):1.9031,1.8451,1.7782,1.6990,1.6021
Log T*10^-2(s):24.83,21.33,19.28,15.91,12.12
Log L*10^-1(cm):19.031,18.451,17.782,16.990,16.021
SLOPE(s)=(LogT2*10^-2 – LogT1*10^-2)(/Log L2 *10^-1 – LogL1*10^-1)
=(21.33-12.12(s))*10^-2/(18.50-16.02(cm)*10^-1)
=3.714*10^-1
=0.3714cm^-1
(1axi)
(i) I ensured supports of pendula were rigid
(ii) I avoided parallax error on the meter rule
(1bi)
Simple harmonic motion is the motion of a body whose acceleration is always direct towards a fixed point and is proportional to the displacement from the fixed points
(1bii)
T=1.2secs
Log 1.2=0.079
0079 shown on graph with corresponding Log L read L correctly determined
==========================================
(3a)
TABULATE:
x(cm):10,20,30,40,50,60
V(v):0.65,0.75,1.00,1.20,1.45,1.55
I(A):0.20,0.30,0.35,0.40,0.45,0.55
LogV(v):-0.187,-0.125,0.000,0.079,0.161,0.190
LogI(ohm):-0.699,-0.523,-0.456,-0.396,-0.391,-0.360
SLOPE(s):=( LogI2-LOgI1)/(LogV2-LogV1)
=-0.2-(-0.7)/0.3-(-0.2)
=0.5/0.5
=1AV^-1
(3axi)
(i) I ensured neat and tight terminals
(ii) I opened the key when reading was taken
(3bi)
(i)The brightness of the bulb increases
(ii) The voltage and current through the bulb increases
(3bii)
(i) diode
(ii) transistor

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History answers now posted

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Economics now posted

[10:31AM, 9/16/2017] El Supremo: 4a)
Production is a process of combining various material inputs and immaterial inputs (plans, know-how) in order to make something for consumption (the output). It is the act of creating output, a good or service which has value and contributes to the utility of individuals

b)
Primary industries are industries, such as mining, agriculture, or forestry, that is concerned with obtaining or providing natural raw materials for conversion into commodities and products for the consumer

*WHILE*

Secondary industries are industries that converts the raw materials provided by primary industry into commodities and products for the consumer; manufacturing industry.
Feedback
[10:31AM, 9/16/2017] El Supremo: 5a The money market is where financial instruments with high liquidity and very short maturities are traded. It is used by participants as a means for borrowing and lending in the short term, with maturities that usually range from overnight to just under a year.
5b (i) Treasury bill is a short-dated government security, yielding no interest but issued at a discount on its redemption price.
5b (ii) Treasury certificate is another money instrument which and in the mobilization of savings, which is made available to the needy sectors of the economy. It is a medium-term government security which matures after a period of one to two years and it is intended to bridge the gap between the treasury bill and long-term government securities.
[10:31AM, 9/16/2017] El Supremo: 5c 1. To maintain monetary balance between demand and supply of short term monetary transactions.

2. Money market plays a very important role of making funds available to many units or entities engaged in diversified field of activities be it agriculture, industry, trade, commerce or any other business.

3. By providing funds to developing sectors it helps in growth of economy also.
[10:31AM, 9/16/2017] El Supremo: 5b (iii) A debenture is a type of debt instrument that is not secured by physical assets or collateral. Debentures are backed only by the general creditworthiness and reputation of the issuer
[10:31AM, 9/16/2017] El Supremo: 4a)
Production is a process of combining various material inputs and immaterial inputs (plans, know-how) in order to make something for consumption (the output). It is the act of creating output, a good or service which has value and contributes to the utility of individuals

b)
Primary industries are industries, such as mining, agriculture, or forestry, that is concerned with obtaining or providing natural raw materials for conversion into commodities and products for the consumer

*WHILE*

Secondary industries are industries that converts the raw materials provided by primary industry into commodities and products for the consumer; manufacturing industry.
Feedback
[10:35AM, 9/16/2017] El Supremo: *Nigeria only*

7ai)

Terms of trade:

Terms of trade is the ratio of an index of a country's export prices to an index of its import prices.

ii) Balance of trade:

Balance of trade is the difference in value between a country's imports and exports.
[10:44AM, 9/16/2017] El Supremo: *Nigeria only*

7ai)

Terms of trade:

Terms of trade is the ratio of an index of a country's export prices to an index of its import prices.

ii) Balance of trade:

Balance of trade is the difference in value between a country's imports and exports.
[10:44AM, 9/16/2017] El Supremo: Ghana

7a)

An industrial estate is a place where the required facilities and factory accommodation are provided by the government to the entrepreneurs to establish their industries there
[10:52AM, 9/16/2017] El Supremo: 5a).
The money market is where financial instruments with high liquidity and very short maturities are traded. It is used by participants as a means for borrowing and lending in the short term, with maturities that usually range from overnight to just under a year. Among the most common money market instruments are eurodollar deposits,
negotiable certificates of deposit (CDs) , bankers
acceptances , U.S. Treasury bills, commercial paper,
municipal notes , federal funds and repurchase agreements (repos).

5b).
ii).
*Treasury Bills:*
Treasury Bills are short-term debt instruments issued by the Federal Government through the Central Bank to provide short term funding for the government. They are by nature, the most liquid money market securities and are backed by the guarantee of the Federal Government.

ii).
*Treasury Certificate:*
A debt security issued by the U.S. Treasury with a short
maturity , usually only a few months, and a rather unusual interest rate , such as 4.586%. They are no longer issued to the public and are only issued at all when the Treasury seeks to borrow from the Federal Reserve. In that situation, the Treasury issues Treasury certificates to the New York Federal Reserve Bank; this can only occur with the approval of the Fed's Board of Governors .

iii).
*Debenture:*
They are means with which limited liability companies borrow funds on medium term basis (5-10 years). They bear fixed rate of interest. They are redeemable (paid back) at the end of the agreed period like 10 years.

*5c)*
i). It makes money available to businessmen, especially creditors by discounting their bills
ii). It raises the level of economic activities.
iii). It makes money available to the government through sales of Treasury Bills.
[10:52AM, 9/16/2017] El Supremo: 3a)
Labour force can be defined as the total number of people within the productive sector that are gainfully employed and thos of them that are not gainfully employed.

(3b)
(i) Structural unemployment: It is the type of unemployment that exist when there is changes in the level of technology which affects productivity or output
(ii) Frictional unemployment: It exists when workers intend to change their jobs and they are not adequately informed by opportunities existing in other places.

(3c)
(i) The population of the country
(ii) The percentage of the population that are gainfully employed
(iii) The availability of good medical facilities
(iv) The total number of productive hours worked

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Gce chemistry now posted

WAEC GCE - CHEMISTRY PRACTICAL ANSWERS
Exam Time: Friday, 15th September, 2017
Chemistry 3 (Alternative to Practical)
9.30am – 11.00am
===============================

++++++++++++++++++++++++++
COMPLETED
++++++++++++++++++++++++++

(1ai)
Burette Reading(cm^3)| 1 | 2 | 3 |
Final Reading |33.10|30.00|25.00|
Initial Reading | 9.60|7.50 |2.40 |
Volume of F used (cm^3)|23.50|22.50|22.60.

(1aii)
Average volume of F used
=22.50 + 22.60 / 2
=22.55cm^3

(1bi)
GIVEN:Molar Conc of Kmn04 =0.200mol/dm^2
Volume of Kmn04 used =22.55cm^3
Molar Conc of FeSo4. 7H2O=?
Volume of FeSO4.7H2O=25cm^3
Mole ratio of Kmn04 =1
Mole ratio of FeSO4.7H2O=5

Using,
Molar Conc of KeSO4.7H2O x Volume(FeSo4.7H2O) =n(FeSO4.7H2O)/n(KmnO4)

=molar Conc x 25 / 0.0200 x 22.55 = 5/1

=Molar Conc. x 25=0.0200 x 22.55 x 5
=Molar Conc =0.0200 x 22.55 x 5 / 25

=Molar Conc =0.0902mol/dm^3

(1bii)
Molar mass of FeSO4.7H2O
=56+32+(4*16)+7(18)
56+32+64+126 = 278g/mol
Conc of FeSO4.7H2O in gdm-3 = 0.0900*278
=25.02gdm-3

(1biii)
Mass of FeSO4.H2O = 33.60-25.02
=8.58gdm-3
Percentage of FeSO4.7H2O = (8.58/33.60) * 100
= 25.54%

(1ci)
Hydrochloric acid(HCL) is a mild reducing agent and so it will consume a certain amount of Kmn04 during titration. This will give a slightly higher value of Kmn04 consumption than the actual amount needed by the analyte

(1cii)
As Kmn04 is a dark purple colour solution, it is not possible to take readings from the button of the meniscus on the burette as in usual. Hence, the top, of the meniscus is used(visibility consideration)

(1ciii)
No indicator is used because Kmn04 serves as an indicator

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

(2a)
TEST|OBSERVATION|INFERENCE

(2ai)
TEST: A+distilled water and stirred
OBSERVATION: A disolved in water
INFERENCE: A is soluble in salt

(2aii)
TEST: A(aq)+litmus paper
OBSERVATION: Turns blue litmus paper red
INFERENCE: A is an acidiic salt

(2aiii)
TEST: A(aq)+NaOH(aq)- in drops, then in excess
OBSERVATION: -White gelatinous ppt formed.
-Precipitate soluble/dissolved
INFERENCE: Pb^2+ or Zn^2+ or Al^3+ present
Pb^2+ or Zn^2+ or Al^3+ present

(2aiv)
TEST:A(aq)+NH3(aq)- in dropss,
-then in excess
OBSERVATION: -White gelatinous precipitate
-Precipitate insoluble
INFERENCE: -Pb^2+ or Zn^2+ or Al^3+
-Al^3+ present
(2av)
TEST: A(aq)+FeSO4(aq)+conc H2SO4
OBSERVATION: Brown ring forms between the two solutions
INFERENCE: NO3- confirmed

(2bi)
A is aluminium trioxonitrate(v)

(2bii)
Al(NO3)3

(2c)
TEST|OBSERVATION|INFERENCE

(2ci)
TEST: K+NaHCO3(aq)
OBSERVATION: No visible reaction is observed
INFERENCE: NaHCO3(aq) does not show result for alkanols(K)

(2cii)
TEST: K+benedict solution+heat
OBSERVATION: There is no change in the colour of the benedicts solution
INFERENCE: Benedicts solution is not an indicator for alkanols(K)

(2ciii)
TEST: K+KMnO4(aq)
OBSERVATION: KMnO4(aq) solution changes from purple to colourless
INFERENCE: Alkanol is being oxidized by KMnO4

(2civ)
TEST: K+CH3COOH+conc H2SO4
OBSERVATION: pleasant fruity smell is observed
INFERENCE: Esterification reaction has occured

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

(3a)
(i) Putsome distilled water in a beaker
(ii) Measure 100cm^3 of 2.00mol/dm^3 of the stock solution by means of a burette and pour all the solution into the beaker containing the distilled water
(iii) Stir the solution
(iv) Transfer the solution into a 250cm^3 volumetric flask by means of a funnel
(v) Ensure that all the solution in the volumetric flask has been transferred by thoroughly rinsing the inside of the beaker with distilled water
(vi) Dilute the solution in the volumetric flask with distilled water until it reaches the 250cm^3 mark
(vii) Shake the solution carefully

(3b)
(i) CH3COONa: It forms basic solution
(ii) Al2(SO4)3: Acidic solution
(iii) KNO3: Neutral solution

(3c)
Acidified potasium tetraoxomanganate(vii) KMnO4 was placed in the burette

++++++++++++++++++++++++
COMPLETED
+++++++++++++++++

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Physics obj

PHYSICS OBJ:
1ABABDBBBBC
11CCCDADCABA
31ADBCDACBBB

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Please kindly Subscribe For *Geography3* Answer Now..
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Physics answers now posted

: 8ai)
Force is a push or pull which changes a body state of rest or of uniform motion in a straight line
8aii)
The two types of force are
*constant force
*field force
*magnetic force
*gravitational force
=====
5)
i)availability of constant sunlight
ii)nearness to power grid
iii)must be closer to both skilled and unskilled labour
[10:06AM, 9/14/2017] Waka Gist Admin: *Question one*
(a)  Horizontal speed just before it strikes floor = ucos(theta)
                                                                                    = 10cos0°
                                                                                    = 10 m/s

(b) t = √(2g/h)
        = √(2*10*1)
        = √20
        = 4.47s

Question 4
(a)  given: u = 20m/s
                   t = 4s
                   g = 10m/s²
                   h = ?
    Using s = ut - ½gt²
               s = 20(4) - ½(10)(4)²
               s = 0m

(b)   The inference is that after 4s, the ball returns back to the plane of projection

Question 3
Magnetic materials: ¶ Iron ¶ Cobalt ¶ Nickel

Question 2
¶ medical uses
¶ welding and cutting
¶ military uses for defense and counter measures

Question 5
The factors that determine the location of a solar power station are
¶ Intensity of sun light
¶ surface slope
¶ feeder capacity of the distribution center

Question 11
(a)  ¶ Electrical method
       ¶ Contact method

(b)  Electric lines of force are imaginary lines drawn in an electric field in such a way that the direction at any point gives the direction of the electric field at such a point

(c)  QR = SP

(d)  Resistivity is the resistance of a unit length of material of unit cross-sectional area

(e)  Given: F = 50Hz
                   L = 10 mH (10×10^-³H)
       Inductive reactance, XL = 2πFL
                                                  = 2×3.14×50×10×10^-³
                                                  = 3..14 ohms

(f)  If voltmeter reads 12V, over the 500 ohms, then using I = V/R
                                                            current in the circuit is I = 12/500
                                                                                                     I = 0.024A
     Hence over the 200 ohms, V = IR
                                                    V = 0.024×200
                                                    V = 4.8 VOLTS
     Voltmeter will read 4.8 volts

*Question 9*
(a) Poor conductors of heat application: ¶ Coat (Trapped air in between the fabric)
                                                                        ¶ The hair and the fur of animals are bad conductors of
                                                                            heat and they protect them from cold .

(b) Renewable: Water, corn stalk
     Non-renewable: coal, natural gasgas

(c) A closed is a physical system so far removed from other systems that it does not interact with them.

d)  heat required to melt = mc∆ + ml
    *NB*: Not sure of the temperature given, if it is -3°C or -5°C, However, *Using -3°C*
Heat = (0.1×2200×3)+(0.1×2.26×10^6)
           = 226660 J

e) (i) Given:  75 heart beats in 1 min
                      Therefore in 1 hour, we have (75×60) heart beats = 4500 heart beats
         Also given:  2J of energy is expended in 1 heart beat
                       Therefore for 4500 heart beats, energy expended = (4500×2) J = 9000J

e) (ii)  Energy = mc∆
           9000 = (0.25×4200×∆)
           9000 = 1050∆
           ∆ = 9000/1050
           Temperature rise = 8.57°C

Question 8

a)(i) A force is anything that causes motion
(ii) ¶ contact force
      ¶ field force

b)(i)  Bodies are streamlined so they can overcome to a great extent the viscosity that exists in fluids
   (ii) ¶ submarines
         ¶ seals

8c
i) ¶ Fg is downwards
    ¶ T1 is upwards

ii) ¶ a = v²/r
       a = 7²/1.2
       a = 40.8 m/s²

    ¶ F = ma
          = 1.3 × 40.8
          = 53N: SECTION-A ANS 5 ONLY
================================
4a)
Time (t)=4secs
V=0ms^-1
pie call,V^2=U^2+2gh
O^2=20^2+2(-10)h
0=400-20h
20h/20=400/20
h=20m
4b)
the magnitude of the initial speed (u) is equal to the magnitude of the height attained
================================

================================
2)
i)used ineye surgery
ii)used for the precise cutting of flat material
iii)used for measuring distances
================================
3)
i)iron
ii)steel
iii)nickel
================================
5)
i)availability of constant sunlight
ii)nearness to power grid
iii)must be closer to both skilled and unskilled labour
================================
Keep Refreshing
Typing/Solving
: (6)
P-type semi conductors are created by dopung an intrisic semi conductor with acceptor impurities.
================
: 1.
(a) Horizontal speed just before it strikes floor = ucos(theta)
= 10cos0°
= 10 m/s

(b) t = √(2g/h)
= √(2*10*1)
= √20
= 4.47s
=============================

2
- medical uses
- welding and cutting
- military uses for defense and counter measures
================================

3.
Magnetic materials:
- Iron
- Cobalt
- Nickel
===============================

4.
(a) given: u = 20m/s
t = 4s
g = 10m/s²
h = ?
Using s = ut - ½gt²
s = 20(4) - ½(10)(4)²
s = 0m

(b) The inference is that after 4s, the ball returns back to the plane of projection
===============================

5.
The factors that determine the location of a solar power station are
- Intensity of sun light
- surface slope
- feeder capacity of the distribution center
===============================

8a)
i. Force is a push or pull which changes a body's state of rest or uniform motion in a straight line.

ii.
a) field force
b) contact force

8b)
i. Bodies streamlined in
Shape move through fluid so as to oppose or overcome the motion of the fluid

ii.
a) fish
b) submarine

8c)
Mass= 1.3 kg
F= 1.2 m
V= 7.0 m/s

Drawing

ii. Acceleration
Note , V²= U² + 2as

Where S=r=1.2 m

(7.0)²= 0²+2× a (1.2)

= 49/2.4 = 2.4a/2.4

a = 20.4

B) Force=?
From force = MA
Force =1.3×20.4
Force =25.52
===============================

9)
(a) Poor conductors of heat application: - Coat (Trapped air in between the fabric)
- The hair and the fur of animals are bad conductors for heat and they protect them from cold .

(b)
Renewable: Water, corn stalk
Non-renewable: coal, natural gas

(c) A closed is a physical system so far removed from other systems that it does not interact with them.

d) heat required to melt = mc∆ + ml
Note: Not sure of the temperature given, if it is -3°C or -5°C, However,
Using -3°C
Heat = (0.1×2200×3)+(0.1×2.26×10^6)
= 226660 J

e)
i. Given: 75 heart beats in 1 min
Therefore in 1 hour, we have (75×60) heart beats = 4500 heart beats
Also given: 2J of energy is expended in 1 heart beat
Therefore for 4500 heart beats, energy expended = (4500×2) J = 9000J

ii. Energy = mc∆
9000 = (0.25×4200×∆)
9000 = 1050∆
∆ = 9000/1050
Temperature rise = 8.57°C
================================
11)

(a)

- Electrical method
- Contact method

(b) Electric lines of force are imaginary lines drawn in an electric field in such a way that the direction at any point gives the direction of the electric field at such a point

(c) QR = SP

(d) Resistivity is the resistance of a unit length of material of unit cross-sectional area

d) heat required to melt = mc∆ + ml
Note: Not sure of the temperature given, if it is -3°C or -5°C, However, *Using -3°C*
Heat = (0.1×2200×3)+(0.1×2.26×10^6)
= 226660 J

(e) Given: F = 50Hz
L = 10 mH (10×10^-³H)
Inductive reactance, XL = 2πFL
= 2×3.14×50×10×10^-³
= 3..14 ohms

(f) If voltmeter reads 12V, over the 500 ohms, then using I = V/R
current in the circuit is I = 12/500
I = 0.024A
Hence over the 200 ohms, V = IR
V = 0.024×200
V = 4.8 VOLTS
Voltmeter will read 4.8 volts

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Uniport cancles post utme date

This to inform all prospective Students of University of Port-

harcourt (UNIPORT) that owing to unforeseen circumstances,

that the 2017/2018 Screening Exercise scheduled to

commence on the 14th September, 2017, has been postponed.

A new date will be communicated in due course.

Candidates are therefore advised to visit the University

website for further information in this regard. Registration for

the Screening is still on going.

Any inconvenience caused by this postponement is regretted.

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