₦airaland Forum

Gracy3535:
A ball is thrown vertically upwards from the ground with an intial velocity of 50m/s. What is the total time spent by the ball in the air (g=100ms-2). Please i need the working.A ball is thrown vertically upwards from the ground with an intial velocity of 50m/s. What is the total time spent by the ball in the air (g=100ms-2). Please i need the working.

.....this is a very simple free fall question...we can calculate it in 2 ways....one is 2 step way and other is simple one step way( using formula)..let's do it d simple way first.... The time it spent in air is the time of flight represented as T....T= 2u/g......2 * 50/ 10 = 100/ 10... = 10s...

Gracy3535:
A ball is thrown vertically upwards from the ground with an intial velocity of 50m/s. What is the total time spent by the ball in the air (g=100ms-2). Please i need the working.A ball is thrown vertically upwards from the ground with an intial velocity of 50m/s. What is the total time spent by the ball in the air (g=100ms-2). Please i need the working.

..gracy, thanks for quoting me but u could av just posted the ques....quoting me may nt allow others to solve it...there are many bosses and guru on this thread...

[quote author=Aybalance post=66615315][/quote]..bro,how r u doing..how is ur prep? .
It is supported at one end..not both end...in my earlier post,av stated that at the pivot..the force is Zero...the total force acting is in the middle( at the centre)...try to visualize it...let's talk 2ru email l8ta...

vicstiqs95:
1.which of the following cannot be made by green plants? A. vitamins B. fats C. carbohydrates D. minerals E. proteins.

..fats

vicstiqs95:
muscular dystrophy is sex- linked.

...thanks..I don't know that....

Orezy5:
BIOLOGY


(GENETICS : SEX DETERMINATION AND SEX-LINKED CHARACTERS)


1. If a baby is a female, her mother's ovum must have been fertilized by a sperm carrying the chromosome
a. X
b. XY
c. YY
d. Y


2. In which of the following crosses will all the female offspring be colour blind?
a. colour blind mother x colour blind father
b. colour blind mother x normal father
c. carrier mother x colour blind father
d. carrier mother x normal father


3. A sex linked trait can never be transmitted from
a. mother to daughter
b. father to son
c. mother to son
d. father to daughter


4. Which one of the following characteristics is not sex linked?
a. colour blindness
b. baldness
c. haemophilia
d. muscular dystrophy
e. none of the above


5. Which of the following is true of the children of a haemophilic man who marries a woman that is not haemophilic and does not carry the trait?
a. all their sons will be haemophilic
b. all their daughters will be haemophilic
c. all their daughters will be carriers
d. all their sons will be carriers


6. Women do not suffer from colour blindness because
a. the trait is sex linked
b. only men are colour blind
c. the genes are recessive and sex linked
d. the genes occur on both the X and Y chromosomes


7. The pair of colours that cannot be distinguished by a person suffering from colour blindness is
a. white and blue
b. yellow and green
c. red and blue
d. red and green
e. yellow and red


8. At what stage in the life history of a mammal is the sex of an individual set?
a. at puberty
b. at birth
c. at conception
d. during meiosis
e. at adolescence


9. Which of the following is a diploid cell?
a. spermatogonia
b. spermatozoa
c. ovum
d. spermatids
e. none of the above

Afternoon Bosses

1..A..2..A..3..B..4..D..5..C..6...C..7..D.. 8...C..9...A

dannyboii1:
what textbook do u make use of

lamlad physics and science physics

Que 7...we can use 2 formula...but lemme simplify it...since the body is coming to rest...the total net force acting on it is only the frictional force....fnet = ma..fnet= fr..so fr= ma...let's get a first...vsquare = usquare + 2as...vsquare = 0.. Since the crate came yo rest....then, usquare = 2as..a= usquare/2s..... u is 3..while s is 2.5...a= 9/ 5 which is = 1.8...fr = ma...fr = umg...so,
umg = ma....ug = a ..u= a/g..= 1.8/ 10 ...u =0.18..

ques 5.... net force = ma...net force = force applied - frictional force..... So,..
fa - fr= ma..but fr = umg.....fa- umg = ma....8.75 - ( 3.5 * 0.2 *10)= 3.5a...8.75- 7 = 3.5a..1.75 =3.5a...a= 1.75/3.5...a= 0.5..

ques 4...10 * x =40(100- x)..10x =4000 -40x...10x+40x =4000....50x = 4000...x = 80cm

For others ...que 2....( 0.2 * 30)+ W * 10 =0.5 *20... 6 +10W = 10.....10 - 6 =10W.....4 =10W.....W=0.4N..

vicstiqs95:
Pls I will love to see the correct workings for no.1 and 3. don't really understand it.

...No..3.....on a uniform metre rule,the total weight lies at the centre...a uniform rule is always 100 cm or 1m.....the plank weighed 1.5kg or 15N.. The centre of 100 cm plank is 50cm....another weight of 7N is place at the centre or at 50cm...total weight is now= 15N+ 7N= 22N...we are asked the upward force that will balance the downward force....since the downward force = 22N...upward force= 22N

vicstiqs95:
Pls I will love to see the correct workings for no.1 and 3. don't really understand it.

No 1...(200 * 2) + (40 * 15) =4N.........400+600=4N... 1000=4N...N= 250....the whole weight of the plank = 600N....the upward force has to balance the downward force...so..the downward force= 600N...one of the upwar force which is the reaction = 250 N...the other reaction will = 600- 250= 350N......the concept is that you av to take your pivot at one of the reaction...where you take your pivot,the force there will be ignore or considered as Zero.........m sori...can't explain beta...

Orezy5:
PHYSICS (EQUILIBRIUM OF FORCES)
1. A uniform beam of length 4m and mass 20kg is supported at both ends. A girl of mass 40kg stands on the beam at a distance of 1.5m from one of the supports. The reactions at the supports are
a. 150N, 250N
b. 250N, 350N
c. 200N, 300N
d. 300N, 300N


2. Weights of 0.2N and 0.5N are placed at the 30cm and 80cm marks respectively on a uniform metre rule. If the metre rule balances horizontally on a knife edge at the 60cm mark, the weight of the metre rule is
a. 0.4N
b. 0.1N
c. 3.3N
d. 0.7N


3. A uniform metre rod of mass 1.5kg is pivoted at one end. A weight of 7N is placed at the 50cm mark of the rod. The vertical force which should be applied at the other end to maintain the rod in equilibrium in the horizontal position is
a. 22N
b. 10.6N
c. 8.5N.
d. 11N


4. A mass of 10g Is attached to the 0cm mark of a light metre rule while a mass of 40g is attached to the other end. The centre of gravity of the system is located at the
a. 20cm mark
b. mid point of the metre rule
c. 60cm mark
d. 80cm mark


5. A force of 8.75N is applied to a mass of 3.5kg placed on a horizontal surface. If the coefficient of friction is 0.2, the acceleration of the mass is
a. 0.5m/s²
b. 1.0m/s²
c. 1.5m/s²
d. 3.3m/s²


7. A crate of mass 25kg moving with a speed of 3m/s on a rough horizontal floor is brought to rest after sliding a distance of 2.5m on the floor. The coefficient of sliding friction is
a. 0.09
b. 0.18
c. 0.36
d. 0.25

..1...B (250N,350N)...2..A ( 0.4N)...3..A (22N)...4..D (80 cm mark)..5..A..(0.5N)...7...B (0.18)....

Eben331:
Pls guys I need help in the this question 1 The Chairman, Committee of Deans needs to see your friend Dele urgently, do you know his __? A where and about B whereabouts C whereabout D where and abouts

..B...just like scissors,surrondings e.t.c whereabouts alw have a (s)

dannyboii1:
generally rise of 10°C.... of the temperature of a reaction system,..... the reaction rate

A. increases
B. doubles
C. subsides
D. drops

...B..

IamGoke:
I need your solving bro... mine was just wuruwuru to d answer!
thanks!

..OK bro BT let's wait for yusman to solve it...

yusman14:
working/solution loading.....

..OK..solve it then..if u are wrong,I will resolve it...

yusman14:
oh..miztake..its 0.4..option C

...nice try sir..know u guys will eventually get it..that's human power..

IamGoke:
0.4%

correct

Damayogenius18:
A wire is stretch to make it 0.2% longer....what is the percentage change in resistance....(A) 10% (B)0.2% ( C)0.4% (D)5%

...Papi112, DrBest,eben13,medical guys...where art thou.....

yusman14:
d

...wrong bro..

dannyboii1:
From the formula resistance =resistivity *lenght/areA


Dat means as resistance increases length also increase... Therefore if resistance increases by 0.2% length also increase by 0.2%

..I know many will stumble at the question.. Dat's y I asked..if it was that simple,I wouldn't av asked...u should know that by now...

Orezy5:
I also got 0.2%..

..boss.. Are you also coming for ui medicine or oau The answear you got its wrong....I will solve it b4 the day runs out BT let's give opportunity to others....m sure someone will solve it rightly

afoobabs:
are you a doc or a pastor. this gets me motivated

...both...lol..

boyejo124:
morning house
Welldone to everyone
a friend of mine scored 207 and wanna study computer science,what are his chances

..Fight! Fight!!
...that's what we must all do before we can attain that height and get the price.
(Quote)

Teekzel:
B

pls give ur working boss....you are wrong though...

Pes13:
True.

I wish everybody on nairaland well but not everybody on nairaland will pass Putme. Bitter but true

Even that said, not everybody that pass Putme will be admitted.

And not everybody that is admitted will be gracious to study their dream course just because they couldn't meet the cut. MBBS, BDS, llb, economics, vet, engr aspirants are the top victim of this.

Many aspirants here will still scream and fight for change of course after cutoff mark is released.

That course people see as a lazy man course will be more competitive and sought after than medicine and surgery during Change of course.

You will see law aspirants who would have fought anyone that advise them to study History fight for this same history just because of 1 mark shot of the cutoff for law.

Its a matter of survival of the fittest/finest.

I don't want to sweet mouth people alone and make it look the battle ahead is a bed of rose.

This is the time to sacrifice the next three-four months for intensive study. Pay the price, burn the mid-night candle if you can, sacrifice the time you spend on social media and watch yourself triumph.

Remember the books you are reading is the same books everybody is reading, it now down to your understanding and your smartness. I wish every nairalander best of luck.

....boss, we will surprise you this time...am speaking on behalf of all of us...we will all get our respective courses...but has boss said,let us all shun social network...

Preparation is a daily thing..we fail daily and we succeed daily...we don't fail or succeed the day we write post utme...the failure and success we get is the accumulation of what we have been doing per day..........if you want to know if you will get MBBS or not,look at what you are doing per day...

A wire is stretch to make it 0.2% longer....what is the percentage change in resistance....(A) 10% (B)0.2% ( C)0.4% (D)5%

Papi112:
He is back ooo
My boss is back
Welcome sir

I think na perfect conductor c...
It is a conductor dat as zero resistivity or resistance and non ending electrical flow...
I stand to be corrected

..yea..correct doc..I really wanna trap you by putting superconductor in the options......superconductor also has zero resistance bt there is a clause.........lemme ask u doc...what did you think you will score in post utme...

Which of these has zero resistance..(A) semi conductor (B) super conductor (C) perfect conductor (D) conductor