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 Education / Re: 2018/2019 Admission Process Thread Guide by DrBESTJC(m): 4:49am On Jul 19, 2018 |
BiafranDel: Visite the UI 2018/2019 Admission Thread to get more of it. I can't post all here. Serious UI PostUTME exam preparations are going on in that thread. |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 4:32am On Jul 19, 2018 |
Aceed: Answer: C Reason Charring of sugar is the dehydration of sugar either by heating it in the abscence of air or by heating it strongly with concentrated tetraoxosulphate(VI) acid to produce a black mass of carbon(known as char) and water. |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 4:16am On Jul 19, 2018 |
Aceed: Answer :B (walking) Reason Cerebellum, sometimes called the little brain , lies below the back of the cerebrum. It is oval in shape and consists of two hemispheres. It is less convoluted than cerebrum and are shallower and less irregular (more or less parallel) than those of cerebrum. The surface of cerebellum is covered with grey matter , while the inner side is composed of white matter. It is connected to the semi-circular canals of the ears. Functions of the Cerebellum 1) It is concerned with the balance and positioning of the body, it receives impulses from semi-circular canals of the ears, through the vestibular nerve fibre. 2) It is the coordinator of various actions of muscles in voluntary responses such as walking, talking and sitting. 1 Like |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 3:54am On Jul 19, 2018 |
Aceed: A. Reason Growth is the irreversible increase in volume(size),number of parts,lenght and weight of an organism. |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 3:40am On Jul 19, 2018 |
Aceed: Lol...I just de learn to be humble.....But the 'oga' cloth wey I go wear one day one day na my Martriculation gown on my Matriculation Day  Only God knows how 'madly' joyful I will be on that day.....U no go understand... Person don suffer for this Niger.... But things go better one day! |
| Education / Re: 2018/2019 Admission Process Thread Guide by DrBESTJC(m): 3:32am On Jul 19, 2018 |
Corrections. The correct answers are in Bold DrBESTJC: |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 6:04pm On Jul 18, 2018 |
Quick Revision Questions in CHEMISTRY Answer all 25 questions in 20 minutes ! Test of Speed and Accuracy Typical UI PostUTME questions Exam is already here ! 1) The filter in a cigarette reduces the nicotine content by... ? A) adsorption B) absorption C) burning D) evaporation. 2) What mass of K2CrO4 is required to prepare 250cm^3 of 0.020 mol per dm^3 solution...? A) 97.10g B) 19.42g C) 9.70g D) 0.97g [K2CrO4 = 194.2g per mol] 3) The type of reaction that is peculiar to Benzene is...? A) hydrolysis B) addition C) substitution D) polymerization 4) Carbohydrates are compounds containing carbon, hydrogen and oxygen in the ratio of...? A) 1 : 1 : 1 B) 1 : 2 : 1 C) 2 : 1 : 1 D) 3 : 1 : 1 5) How many isomers does pentane have...? A) 4 B) 3 C) 5 D) 6 6) What volume of gas is evolved at s.t.p. if 2g of calcium trioxocarbonate (IV) is added to a solution of hydrochloric acid...? A) 112 cm3 B) 224 cm3 C) 448 cm3 D) 2240 cm3 [ Ca = 40, C = 12, O = 16, CL = 35.5, H = 1, Molar volume of a gas at s.t.p. = 22.4 dm3 ] 7) According to Charles's law, the volume of a gas becomes zero at...? A) 0 degrees centigrade B) -100 degrees centigrade C) -273 degrees centigrade D) -373 degrees centigrade 8 ) A given volume of methane diffuses in 20seconds. How long will it take the same volume of sulphur(IV)oxide to diffuse under the same conditions...? A) 5 seconds B) 20 seconds C) 40 seconds D) 60 seconds [C = 12, H = 1, S = 32, O = 16] 9) Chlorine consisting of two isotopes of mass numbers 35 and 37 in the ratio of 3:1 has an atomic mass of 35.5. Calculate the relative abundance of the isotope of mass number 37. A) 20 B) 25 C) 60 D) 75 10) The oxidation state of chlorine in HCLO4 is...? A) -5 B) -1 C) 1 D) 7 11) Which of these compounds is a normal salt...? A) NaHS B) NaHSO4 C) NaHCO3 D) Na2CO3 12) Which of the following acts as both a reducing and an oxidizing agent...? A) H2 B) SO2 C) H2S D) CO2 13) In the electrolysis of brine, the anode is...? A) platinum B) copper C) zinc D) carbon 14) The solubility in mol per dm3 of 20g of CuSO4 dissolved in 100g of water at 180 degrees Centigrade is...? A) 0.13 B) 0.25 C) 1.25 D) 2.00 15) The mass of silver deposited when a current of 10A is passed through a solution of silver salt for 4830 seconds is...? A) 108.0g B) 54.0g C) 27.0g D) 13.5g [Ag = 108, F = 96500 C mol-1 ] 16) The allotrope of carbon used in the decolourization of sugar is ...? A) graphite B) soot C) charcoal D) Lampblack 17) Sulphur (IV) oxide bleaches by...? A) reduction B) oxidation C) hydration D) adsorption. 18 ) Vulcanization involves the removal of ...? A) a monomer B) the single bond C) the double bond D) a polymer 19) CH3COOH (g) ----> CH4(g) + CO2(g) The reaction above is...? A) Carboxylation B) decarboxylation C) acidification D) esterification 20) Alkanol + Alkanoic acid <---(gives reversibly)---> Ester + Water. The reverse reaction of the equation above is known as...? A) hydrolysis B) saponification C) hydration D) fermentation. 21) In the production of soap,concentrated sodium chloride solution is added to...? A) increase the solubility of the soap B) decrease the solubility of the soap C) saponify the soap D) emulsify the soap. 22) The property used in the industrial preparation of nitrogen and oxygen from air is...? A) rate of diffusion B) solubility C) density D) boiling point 23) A dense white fume is formed when ammonia reacts with...? A) Hydrogen gas B) Oxygen gas C) Hydrogen Chloride gas D) Chlorine gas 24) Aluminium hydroxide is used in the dying industry as a...? A) salt B) dye C) mordant D) dispersant. 25) The most suitable metal that can be used as a lightning conductor is...? A) aluminium B) iron C) copper D) silver. |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 10:26am On Jul 17, 2018 |
Quick Revision In CHEMISTRY Solubility of salts in water. Solubility Rules 1) All salts of sodium,Potassium and ammonium are soluble in water. 2) All trioxonitrate (V) salts are soluble in water. 3) All chlorides are soluble in water; except those of Lead, mercury and silver that are insoluble in water. 4) All tetraoxosulphate(VI) salts, are soluble in water ; except those of lead and barium. Calcium tetraoxosulphate (VI), CaSO 4 is only slightly soluble in water. 5) All trioxosulphate (IV) salts are insoluble in water;except those of sodium,Potassium and ammonium that are soluble. 6) All trioxocarbonate (IV) salts are insoluble in water; except those of sodium,Potassium and ammonium that are water-soluble. 7) All sulphides, S2- are insoluble in water; except those of sodium,Potassium and ammonium that are soluble. 8 ) All acid salts are soluble in water. Note: 1) Gases, such as ammonia,NH3 and Hydrogen Chloride, HCL are highly soluble in cold water. Infact, they react with water.Their aqueous solutions are therefore used as laboratory reagents. 2) Gases such as SO2 , NO2 , CL 2 , H2 S , N2O and CO2 are fairly soluble in water; hence, they are not collected over cold water during their laboratory preparations. H2S is collected over warm water. 3) Other gases such as O2 , N2 , H2 and CO are only slightly soluble in water;they can be collected over water. 3 Likes |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 9:27am On Jul 17, 2018 |
Corrections. The correct answers are in bold DrBESTJC: |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 8:37am On Jul 17, 2018 |
Aceed: I no be oga anything ooooo!.....I am your fellow student abeg..... Solutions to your questions: Loading.... |
| Education / Re: 2018/2019 Admission Process Thread Guide by DrBESTJC(m): 10:41am On Jul 16, 2018 |
Quick Revision Questions In BIOLOGY Answer all 25 questions in 20 minutes ! Test of Speed and Accuracy Typical UI PostUTME Questions 1) The cell of an onion bulb can be differentiated from a cheek cell by the presence of: A) Plasmalemma B) Chloroplast C) Cell wall D) Nucleus 2) The membrane surrounding the vacuole in a plant cell is called the: A) Plasmalemma B) Tonoplast C) Nuclear Membrane D) Endoplasmic reticulum 3) The pioneer organisms in ecological succession are usually the : A) Lichens B) Algae C) Ferns D) Mosses 4) The umbrella-shaped fruiting body of a fully developed muchroom is the : A) Mycelium B) Basidium C) Pileus D) Stipe 5) The Cnidoblast cells found in Hydra are used for : A) Reproduction B) Offence and Defence C) Locomotion and Nutrition D) Food collection 6) In Spirogyra, the Pyrenoid : A) Excretes wastes products B) is suspended to cytoplasmic strands C) is mainly used for respiration D) makes the plant skinny to touch E) usually contains starch 7) Amoeba moves by means of : A) Cilia B) Flagella C) Pseudopodia D) swimmerets 8 ) Which one of the following animals is NEVER secondary host of tapeworms ? A) Cow B) Fish C) Pig D) Man E) Bat 9) The mosquito that transmits elephantiasis in humans is the : A) Male Culex B) Female aedes C) Male aedes D) Female Culex 10) In tilapia, the fins lying just behind the gill covers are : A) Caudal B) Pectoral C) Pelvic D) Anal 11) The mammalian organ through which nourishment and oxygen diffuses into a developing embryo is called : A) Amnion B) Chorion C) Umbilical cord D) Oviduct E) Placenta 12) The mammalian vein which starts with and ends in a capillary network is the : A) Pulmonary Vein B) Mesenteric Vein C) Renal Vein D) Hepatic Portal Vein 13) The mode of nutrition in which digestion is extracellular is : A) Holophytic B) Parasitic C) Holozoic D) Saprophytic 14) Insectivorous plants trap and kill their prey to derive : A) Phosphorus B) Calcium C) Nitrogen D) Zinc 15) A young plant showing yellowing of leaves is likely to be deficient in : A) Calcium B) Magnesium C) Potassium D) Boron E) Molybdenum 16) Which vitamin plays an important role in blood clotting ? A) Vitamin A B) Vitamin K C) Vitamin B D) Vitamin C 17) The part of the stomach nearer the gullet is called the : A) Epiglottis B) Cardiac Sphincter C) Duodenum D) Pyloric Sphincter 18) The digestive enzyme that coagulates proteins in milk is : A) Ptyalin B) Pepsin C) Renin D) Trypsin E) Amylase 19) The mammalian heart chamber that pumps blood through the longest distance is the : A) Right Auricle B) Right Ventricle C) Left Ventricle D) Left Auricle 20) Excess water in plants is excreted as water vapour and as droplets respectively through : A) Respiration and Guttation B) Transpiration and Guttation C) Photosynthesis and Guttation D) Guttation and condensation. 21) An organism with double circulation is the : A) Duck B) Rat C) Toad D) Lizard 22) The glottis is the opening which leads to the : A) Oesophagus B) Larynx C) Nostrils D) Pharynx E) Mouth 23) Lung books are used for respiration in : A) Spiders B) Insects C) Millipedes D) Snails 24) The gas produced during tissue respiration can be identified by using : A) Calcium Hydroxide B) Calcium Carbonate C) Copper Sulphate D) Sodium Hydroxide 25) Fatigue of leg muscles may occur after riding many kilometers on a bicycle because of : A) Insufficient Glucose B) Excess carbondioxide C) Excess Protein D) Insufficient oxygen. 1 Like |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 10:33am On Jul 16, 2018 |
Quick Revision Questions In BIOLOGY Answer all 25 questions in 20 minutes ! Test of Speed and Accuracy Typical UI PostUTME Questions 1) The cell of an onion bulb can be differentiated from a cheek cell by the presence of: A) Plasmalemma B) Chloroplast C) Cell wall D) Nucleus 2) The membrane surrounding the vacuole in a plant cell is called the: A) Plasmalemma B) Tonoplast C) Nuclear Membrane D) Endoplasmic reticulum 3) The pioneer organisms in ecological succession are usually the : A) Lichens B) Algae C) Ferns D) Mosses 4) The umbrella-shaped fruiting body of a fully developed muchroom is the : A) Mycelium B) Basidium C) Pileus D) Stipe 5) The Cnidoblast cells found in Hydra are used for : A) Reproduction B) Offence and Defence C) Locomotion and Nutrition D) Food collection 6) In Spirogyra, the Pyrenoid : A) Excretes wastes products B) is suspended to cytoplasmic strands C) is mainly used for respiration D) makes the plant skinny to touch E) usually contains starch 7) Amoeba moves by means of : A) Cilia B) Flagella C) Pseudopodia D) swimmerets 8 ) Which one of the following animals is NEVER secondary host of tapeworms ? A) Cow B) Fish C) Pig D) Man E) Bat 9) The mosquito that transmits elephantiasis in humans is the : A) Male Culex B) Female aedes C) Male aedes D) Female Culex 10) In tilapia, the fins lying just behind the gill covers are : A) Caudal B) Pectoral C) Pelvic D) Anal 11) The mammalian organ through which nourishment and oxygen diffuses into a developing embryo is called : A) Amnion B) Chorion C) Umbilical cord D) Oviduct E) Placenta 12) The mammalian vein which starts with and ends in a capillary network is the : A) Pulmonary Vein B) Mesenteric Vein C) Renal Vein D) Hepatic Portal Vein 13) The mode of nutrition in which digestion is extracellular is : A) Holophytic B) Parasitic C) Holozoic D) Saprophytic 14) Insectivorous plants trap and kill their prey to derive : A) Phosphorus B) Calcium C) Nitrogen D) Zinc 15) A young plant showing yellowing of leaves is likely to be deficient in : A) Calcium B) Magnesium C) Potassium D) Boron E) Molybdenum 16) Which vitamin plays an important role in blood clotting ? A) Vitamin A B) Vitamin K C) Vitamin B D) Vitamin C 17) The part of the stomach nearer the gullet is called the : A) Epiglottis B) Cardiac Sphincter C) Duodenum D) Pyloric Sphincter 18) The digestive enzyme that coagulates proteins in milk is : A) Ptyalin B) Pepsin C) Renin D) Trypsin E) Amylase 19) The mammalian heart chamber that pumps blood through the longest distance is the : A) Right Auricle B) Right Ventricle C) Left Ventricle D) Left Auricle 20) Excess water in plants is excreted as water vapour and as droplets respectively through : A) Respiration and Guttation B) Transpiration and Guttation C) Photosynthesis and Guttation D) Guttation and condensation. 21) An organism with double circulation is the : A) Duck B) Rat C) Toad D) Lizard 22) The glottis is the opening which leads to the : A) Oesophagus B) Larynx C) Nostrils D) Pharynx E) Mouth 23) Lung books are used for respiration in : A) Spiders B) Insects C) Millipedes D) Snails 24) The gas produced during tissue respiration can be identified by using : A) Calcium Hydroxide B) Calcium Carbonate C) Copper Sulphate D) Sodium Hydroxide 25) Fatigue of leg muscles may occur after riding many kilometers on a bicycle because of : A) Insufficient Glucose B) Excess carbondioxide C) Excess Protein D) Insufficient oxygen. 2 Likes 2 Shares |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 8:49am On Jul 16, 2018 |
Eben331: Ok.....Noted. |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 12:02pm On Jul 15, 2018 |
Quick Revision in BIOLOGY Metamorphosis (meta = change ; morphe = form) Metamorphosis is the series of gradual changes that occur during the development of an animal from the zygote(fertilized egg) to the adult stage. The two types of metamorphosis in insects are: 1) Complete metamorphosis : This goes on in four stages which include : Egg ----> Larva ----> Pupa ----> Imago (Adult) . The pupal stage is also known as the resting stage . Examples of insects that undergo complete metamorphosis are houseflies, butterflies, beetles, weevils, bees, ants, wasps, mosquitoes, tsetseflies, blackflies, and moths. 2) Incomplete metamorphosis : This goes on in three stages which include: Egg ---> Nymph ---> Imago. Examples of insects that undergo incomplete metamorphosis are cockroaches, termites, dragonflies, grasshoppers, Locusts, crickets, praying mantis, aphids, cassava mealy bug and cotton stainer. The shedding of exoskeletons at intervals by arthropods [ i.e. Phylum Arthropoda --- which is the largest phylum in the animal kingdom , and is divided into the following classes : Crustacea, insecta( which are the only invertebrates that can fly ), arachnida and myriapoda.] to allow their bodies to increase in size is known as moulting or ecdysis. The enzyme that controls moulting is known as ecdysome Do you still remember the internal structures of an egg?....You might want to revise it in the diagram I drew below... Abeg, click like if you found this revision tips helpful so that I get encouraged to post more..... exam is already here 7 Likes
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| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 11:58am On Jul 15, 2018 |
Eben331: This is Smart!........but very technical and time consuming. And You will still need a calculator to do it, especially when big numbers are involved. 2 Likes |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 11:54am On Jul 15, 2018 |
Eben331: I'm still ruminating over it.I will soon let you know whether or not I was able to solve it. |
| Education / Re: Study In Canada by DrBESTJC(m): 4:07pm On Jul 14, 2018 |
nisimi09: Sir, I sent you an Email but you have not replied...Please it is Very Urgent and Important |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 8:13am On Jul 14, 2018 |
Gracy3535: Yes...but the formula I discovered does not give the exact value....only the approximate value..... |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 9:30am On Jul 13, 2018 |
Aceed: I think it is wrong because tension is a force whose unit is Newton...and spring balance measures weight not mass. But you can still convert the value in Newton to gramms...thus F = mg ...where m = F/g = 0.4/10 = 0.04Kg. Then,multiply by 1000 to convert to gramms = 0.04 * 1000 = 40g |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 7:53am On Jul 13, 2018 |
Aceed:Lol....See this one ..... You never Jam real science Masters.....when you do, you go know say na serious pickin I be for physics.....We just de try small small....I'm aspiring for Medicine. Abeg, post more difficult questions here, let's see how far we have gone.... ...exam is already here |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 7:44am On Jul 13, 2018 |
Aceed: Using the diagramatic reprsentation of the question below, and solving from the resolved triangle of vectors, Cos(theta) = adj/hyp Cos30(degrees) = 7N/T1 .: T1(tension in the long wire) = 7N/cos30 = 8.08N. Also, Tan(theta) = opp/adj. Tan30(degrees) = T2/7N. .: T2(tension in the string) = tan30 * 7N = 4.04N
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| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 7:27am On Jul 13, 2018 |
Aceed: Velocity Ratio = Effort distance/Load distance. From the question, Effort distance = 6.2m ...and Load distance = 3.5m. .: Velocity Ratio = 6.2m/3.5m = 1.77 |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 7:21am On Jul 13, 2018 |
Aceed: From Density = Mass/volume .: Mass = density * volume. From the question,alchohol and petrol have the same mass. .: M = d1 * V1 = d2 * V2. Substituting the values given in the question in the above equation, (8.4 * 10^2)Kg/m^3 * V1 = (7.2 * 10^2)Kg/m^3 * 4.2m^3 .: V1(which is volume of alchohol) = (720 * 4.2)/840 = 3.6m^3 |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 7:09am On Jul 13, 2018 |
Aceed: From Density = Mass/volume .: Mass = Density * volume = 2.5g/cm^3 * 20cm^3 = 50g = (50/1000)Kg = 0.05Kg. Weight of the block in air = mg = 0.05Kg * 10m/s2 = 0.5N. Now, Half of the volume of the block is immersed in water; which implies: 1/2 * 20cm^3 = 10cm^3. Upthrust = density * volume * g(acceleration due to gravity) = 1g/cm^3 * 10cm^3 * g = 10g * g = (10/1000)Kg * 10m/s^2 = 0.01Kg * 10m/s^2 = 0.1N Reading of the spring balance = Tension in the spring of balance = Weight of the block in air - Upthrust = 0.5N -0.1N = 0.4N |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 10:21pm On Jul 12, 2018 |
Aceed: Density of seawater = 1030Kgm^-3. Weight of mine in air = mg = 600g * 10m/s2 = 6000N. Upthrust of mine in seawater = density * volume * acceleration due to gravity = 1030 * 0.8 * 10 = 8240N. Tension in the cable = Upthrust - Weight of mine in air = 8240N - 6000N = 2240N. |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 3:00am On Jul 12, 2018 |
Eben331: Volume of the hydrometer when floating in water,V1 = Volume of the weighted bulb + Volume of the cylindrical stem..... Volume of the wighted bulb = 30cm^3. Volume of the cylindrical stem = §(pie) * r^2(radius squared) * L1. .: V1 = 30cm^3 + §r^2h1. But Cross-sectional area of the cylinder = §r^2 = 1cm^2 (given in the question). Length of the stem immersed when the hydrometer is floating in water,L1 = 3cm. .: volume of the hydrometer when floating in water,V1 = 30cm^3 + (1cm^2 * 3cm) = 30cm^3 + 3cm^3 = 33cm^3. Secondly, Volume of the hydrometer when floating in the Liquid,V2 = Volume of the weighted bulb + volume of the cylindrical stem.... Volume of the weighted bulb = 30cm^3 ........... and Volume of the cylindrical stem = §(pie) * r^2(r squared) * L2 .: V2 = 30cm^3 + §r^2L2. But, cross-sectional area of the cylinder = §r^2 = 1cm^2. Length of the stem immersed when floating in the liquid,L2 = ? .: V2 = 30cm^3 + (1cm^2 * L2 cm) V2 = 30cm^3 + L2 cm^3 Finally, Upthrust = Volume * density * acceleration due to gravity. Which implies that: V1 * d1 * g = V2 * d2 * g Cancell out the acceleration due to gravity,g, we have: V1 * d1 = V2 * d2. From our calculations above,we have that: V1 = 33cm^3 d1(which is density of water) = 1g/cm^3 V2 = (30 + L2) cm^3 d2(which is density of the liquid) = 0.89g/cm^3 Substituting the values in the equation above,we have: 33 * 1 = (30 + L2) * 0.89 33 = 26.7 + 0.89L2 33 - 26.7 = 0.89L2 6.3 = 0.89L2 .: L2 = 6.3/0.89 = 7.1 cm (approximately). Abeg pardon my typos....Na Nokia torch I dey use .....Things go better....1 Like |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 1:52am On Jul 12, 2018 |
TeflonBlixx: Sir,I don't agree with this... I think there is a better way to solve it and arrive at the exact answer...... |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 11:01pm On Jul 08, 2018 |
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| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 10:59pm On Jul 08, 2018 |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 10:54pm On Jul 08, 2018 |
Aceed: i) From V = U - gt (since the body is moving against gravity)... Initial velocity,U, of the second stone is 20m/s. Final velocity,V, of the second stone when they met is 10m/s. .: 10 = 20 - 10t 10-20 = - 10t -10 = - 10t .: t = 1 second. ii) The first stone have travelled for 2 seconds in air before the second stone was projected. The second stone travelled for 1 second before meeting the first stone. From the question,the first stone have reached its maximum height and is now falling back when it met the second stone still rising after 1 second. .: From V = U + gt Where the initial velocity of the first stone when falling from its maximum height is zero and the time it has fallen before metting the second stone is 1 second. .: V = 0 + gt V = gt V = 10 * 1 = 10m/s Since the first stone is now falling down ( ie. moving in a direction opposite to its initial direction),.... .: V = - 10m/s. |
| Education / Re: UI 2018/2019 Admission Thread by DrBESTJC(m): 9:37pm On Jul 08, 2018 |
Aceed: From F = ma But, a = V-U/t .: F = mv-mu/t. Impulse = F * t Which implies that: Impulse = Ft = mv-mu. Final velocity of the ball just before hitting the wall,V, is 5m/s and the initial velocity of the ball after hitting the wall and moving in opposite direction is -(5m/s). .: The impulse of the ball of mass 10kg on the wall = Ft = mv-(-mu) = mv + mu = (10 * 5) + (10 * 5) = 50 + 50 = 100N.s |
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