Nemidav:
thanks!

U are welcome

Nemidav:
I jst messd up!. . .neva knew momentum was = impulse

I woud rather say that u made mistake, but didn't mess up. Come on! Nobody is perfect, we make mistakes everyday. Just keep the good work up.

ANDREW2EIC:

Perhaps u were wrong. I think u unnecessarily prolonged a simple work.
Below is my little explanation to the question:

When a force f(N) is applied on a body of mass m(kg) for a given period of time t(s), the body gains momentum i.e, the massive body moves forward with a certain velocity. The gain in momentum is as a result of force which acts with time. With the already established fact, i can safely say that the gain in momentum is also as a result of impulse on the body. I believe u still remember that impulse is mathematically expressed as: force x time, ft. From law of conservation of energy, energy exhausted for exerted force on the body for a period of time = energy gained by the body to give it momentum.

Hence, impulse = momentum gained, i.e, ft = mv (where m=mass of the body, v = velocity gained. Of course, f is force and t is time taken)

Relating my explanation with the problem at hand, we have:

force exerted by the footballer = 30N, time taken = 0.05s, mass of ball = 0.075kg, velocity= ?.
Substituting:
30x0.05 = 0.075xV, 0.075V = 1.5 (divide both sides by 0.075)
0.075V/0.075 = 1.5/0.075
V = 20m/s.
Therefore, the velocity gained by the ball is 20m/s.

N:B, i only elaborated this much for u to understand what really happened, not that the question is really that difficult.

Hope that helps!

wao @andrew,i've gained from that explanation of yours...
I think it can also be solved this way,
from the law of conservation of energy { F=Mv/t}
since f=30N,M=0.075kg,t=0.05
then make v the subject of the formula and solve.the final answer will be 20 N/s

t.boy007:
wao @andrew,i've gained from that explanation of yours...
I think it can also be solved this way,
from the law of conservation of energy { F=Mv/t}
since f=30N,M=0.075kg,t=0.05
then make v the subject of the formula and solve.the final answer will be 20 N/s

U are on point my guy. If u multiply both sides of that ur equation by t, u wil get the same thing i used.

t.boy007:
wao @andrew,i've gained from that explanation of yours...
I think it can also be solved this way,
from the law of conservation of energy { F=Mv/t}
since f=30N,M=0.075kg,t=0.05
then make v the subject of the formula and solve.the final answer will be 20 N/s

anoda method learnt,thanks

ANDREW2EIC:

I woud rather say that u made mistake, but didn't mess up. Come on! Nobody is perfect, we make mistakes everybody. Just keep the good work up.

thanks alot. . I jst learnt sumfin very valuable 4rm yu.

Nemidav:
anoda method learnt,thanks

thanks alot. . I jst learnt sumfin very valuable 4rm yu.

Honestly, u are such a great guy. Very flexible and willing to learn. These are the qualities that are lacking among us the students, but am really challanged. If you don't mind, which course are u aspiring for and ur preferred institutions?

Ansa z A,cuz evry memba in da group hz an electrn in outa shell wich z responsible 4their reactivity likewis weak metallic bond

t.boy007:
it's soft,(property of group 1 metal)

Sum1 try ds,A Car of mass Mkg is accelratd uniformly frm rest by an engine power P.The minimum time it wil take to attain a speed V is,a.MV/P b.MV/2P c.MV^2/2P d.MV^2/P

Nemidav: Guy i'v a prob wiv diz question. . . . When taking a penalty kick,a footballer applies a force of 30.0N for a period of 0.05s.ifthe mass of the ball is 0.075kg,cal d speed with which the ball moves off.
A.4.50m/s b.11.25m/s c.20.00m/s d. 45.00 m/s

Newton 2nd law of motion, F=m(v-u)/t,
30=0.075*u/0.05
=20m/s (c)

Only argn z used to prvnt oxidatn,nt mxture of argn nd nitrogn

t.boy007:
i think there are two answers there,1=it prevent oxidation in filament lamp and then prevent blackening.but it seems both have thesame meaning chemicaly

ANDREW2EIC:

Honestly, u are such a great guy. Very flexible and willing to learn. These are the qualities that are lacking among us the students, but am really challanged. If you don't mind, which course are u aspiring for and ur preferred institutions?

thanks 4 d nice words . . . i'm goin 4 medicine,uniben. . . I filld d same tin last year bur i was 10% lower dan medicine's cutoff,i was given biology tho. . Bur i turned it down. . . . Wht about you?

Yeah,sam as C i only twstd it!

t.boy007:
i think CaF reduces the melting point during extraction of Ca

Simplefemo:
Newton 2nd law of motion, F=m(v-u)/t,
30=0.075*u/0.05
=20m/s (c)

thanks alot bro. . . GOD BLESS THIS THREAD

I cn see sum1 önline,plz dnt go widout leaving a questn

Obinnau: Answer is A cos the mitochondrion is the power house of the body and its found in d cells.

in this question,u r actually wrong...the answer is D

Nemidav:
thanks 4 d nice words . . . i'm goin 4 medicine,uniben. . . I filld d same tin last year bur i was 10% lower dan medicine's cutoff,i was given biology tho. . Bur i turned it down. . . . Wht about you?

Our good Lord will grant you your heart desire this year. Am going for electrical electronics engineering, futo is my 1st choice while ui is my 2nd. Nice to have u around here.

buzyguy: Sum1 try ds,A Car of mass Mkg is accelratd uniformly frm rest by an engine power P.The minimum time it wil take to attain a speed V is,a.MV/P b.MV/2P c.MV^2/2P d.MV^2/P

My real guy nice to meet u here.
The answer to ur question is c).
Reason: the power of the accelerated car = energy expended by the car/time taken.
But in this case, the energy of the car is all kinetic.
Hence, power(P) = k.e/time(T), P = 1/2MV^2/T. Multiplying both sides by T.
PxT = 1/2MV^2/TxT, PT = 1/2MV^2. Divide both sides by P.
PT/P = 1/2MV^2/P,
Therefore, T = MV^2/2P.

Yeah,whr av u bn snce?u r 2correct!

ANDREW2EIC:

My real guy nice to meet u here.
The answer to ur question is c).
Reason: the power of the accelerated car = energy expended by the car/time taken.
But in this case, the energy of the car is all kinetic.
Hence, power(P) = k.e/time(T), P = 1/2MV^2/T. Multiplying both sides by T.
PxT = 1/2MV^2/TxT, PT = 1/2MV^2. Divide both sides by P.
PT/P = 1/2MV^2/P,
Therefore, T = MV^2/2P.

buzyguy: Yeah,whr av u bn snce?u r 2correct!

I have been around my guy, but didn't know the existence of this thread. I just found it yesterday. Anyways, how is jacking going over there? The D day is almost close

Which of the follown atoms has the follwn,n=3,l=0,m=3orbitals,s=+1/2 or -1/2?a.Na b.Ne c.Al d.Si

Yeah u r rite,bt i stil av lotz to do.may God See us tru!

ANDREW2EIC:

I have been around my guy, but didn't know the existence of this thread. I just found it yesterday. Anyways, how is jacking going over there? The D day is almost close

buzyguy: Which of the follown atoms has the follwn,n=3,l=0,m=3orbitals,s=+1/2 or -1/2?a.Na b.Ne c.Al d.Si

d question is incorect i tink d ans is a. Na since l=0 it means it is s subshell and it suppose 2 av m=0 m=3 refers 2 p orbital with
l=1
s=0(azimutal quantum l)
p=1 (azimutal quantum l)
d=2(azimutal quantum l)
f=3(azimutal quantum l)
remember m=-l,0l

s=0 (magnetic =1)
p=-1,0,1(magnetic no =3)
d= -2,-1,0,1,2(magnetic =5)

so l=0 can not av m=3 quantum number since l= 0 means s orbital also since p orbitals only av m=3

Oh,thks 4ur observatn,itz a graphicl error.l=1 instead ov zero

larri: d question is incorect i tink d ans is a. Na since l=0 it means it is s subshell and it suppose 2 av m=0 m=3 refers 2 p orbital with
l=1
s=0(azimutal quantum l)
p=1 (azimutal quantum l)
d=2(azimutal quantum l)
f=3(azimutal quantum l)
remember m=-l,0l

s=0 (magnetic =1)
p=-1,0,1(magnetic no =3)
d= -2,-1,0,1,2(magnetic =5)

so l=0 can not av m=3 quantum number since l= 0 means s orbital also since p orbitals only av m=3

Wot type of hybridizatn does graphite conform?a.sp b.sp2 c.sp3 d.sp3d

Which molecule hz da least chemical reactivity?a.N b.Cl c.O d.iodine

The likely dude,who needs a thorough nd effective psychiatric attention among our posterz here is ,a.mayorall b.buzyguy c.tboy d.donsnazzy.

buzyguy: Which of the follown atoms has the follwn,n=3,l=0,m=3orbitals,s=+1/2 or -1/2?a.Na b.Ne c.Al d.Si

the value of L can't be 0 since n=3,so L must be definately =2

buzyguy: Which molecule hz da least chemical reactivity?a.N b.Cl c.O d.iodine

a N2 requires +3 which is the highest in the above list to obtain a stable octet configuration

What is the composition of the alloy duraluminium.
a)al,cu,co,fe
b)al,mg,mn,fe
c)al,ni,c,di
d)al,Na,fe,zn

in a light spectrum,which colour has the highest speed?
a)green
b)red
c)blue
d)violet

t.boy007:
What is the composition of the alloy duraluminium.
a)al,cu,co,fe
b)al,mg,mn,fe
c)al,ni,c,di
d)al,Na,fe,zn

in a light spectrum,which colour has the highest speed?
a)green
b)red
c)blue
d)violet

1.B
2.B

Exponential increase in the population of an organism is a characteristic feature of
a. binary fission
b. sexual reproduction
c. budding
d. vegetative propagation

2. A fundamental similarity between nervous and hormonal system is that both
a. involve chemical transmission
b.have widespread effects
c.shed chemicals intothe blood stream
d.evoke rapid responses.

3. 5g of oven dried soil was heated in a furnace for 24 hours. After cooling, it weighed 4.8g. What is the amount of humus in the soil
a. 40.0g per 100g dry soil
b. 4.4g per 100g dry soil
c. 4.0g per 100g dry soil
d. 0.4g per 100g dry soil.

4. During cell division, the two strands of chromosomes are joined at a point called
a. Spindle
b. Chromatid
c. Centromere
d. Aster

ANDREW2EIC:

Our good Lord will grant you your heart desire this year. Am going for electrical electronics engineering, futo is my 1st choice while ui is my 2nd. Nice to have u around here.

yu too. . .tot ui is a federal uni??