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A body moving with uniform acceleration travels 84 metre in 6 seconds and 264 metre in 11 seconds. The initial velocity of the body is

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Ans. Let Initial velocity of body = u m/s
acceleration = a m/s^{2}
According to 2nd equation of motion.
{tex}84 = 6u + {1\over 2}a\times 36{/tex} [{tex}s= ut + {1\over 2}at^2{/tex}]
=> 84 = 6u+18a
=> 14 = u + 3a .............(1)
Also
{tex}264 = 11u + {1\over 2}a\times 121{/tex}
=> 528 = 22u + 121a ...............(2)
multiply eq(1) by 22 and subtract from (2), we get
220 = 55a
=> a = 4, put value of in eq(1)
14 = u + 12
=> u = 2m/s
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A force of 10 Newton acts on a body of mass 2 kilogram for 3 seconds, initially at rest. The velocity acquired by the body will be??

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Solution:
Let initial velocity u = 0
let final velocity v = ?
foce (f) = 10N
Mass of body m = 2Kg
Time t = 3s
Acceleration a = {tex}{vu\over t } = {v0\over 3} = {v\over 3}{/tex}
As we know
f = ma
=> {tex}10 = 2\times {v\over 3}{/tex}
=> v = 15m/s
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A train first travels for 30 minute with a velocity 30 kilometre per hour and then for 40 minutes with a velocity of 40 kilometre per hour in the same direction. The average velocity of train is??
Plz define it also

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Solution : D_{1 }= Distance traveled in 30 minute with velocity 30km/h = 15km
D_{2} = Distance traveled in 40 minute with velocity 40km/h = {tex}80\over 3{/tex}km
Total distance = {tex}15 + {80\over 3} = {125\over 3}{/tex}Km
Total time taken = 30+40 = 70m = {tex}{70\over 60} = {7\over 6}h{/tex}
Average velocity = {tex}{Total\space distance \over time \space taken }= {125 \times 6\over 3\times 7}{/tex}
=,{tex}{250\over 7 } = 35{5\over 7}Km/h{/tex}
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what is the job of mitochondria ? explain with a suitable example?

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The main function of mitochondria is the oxidation of glucose to release energy in form of ATP. It is called as power house of the cell.
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What is circular motion?

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when an object in moving in an circular direction
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In which state of matter, particle motion is the maximum

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In Gaseous State the motin of particle is maximum
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a boy runs for 10 min at a uniform speed of 9km/h . at what speed should he run for the next 20 min.so that the average speed comes to 12km/h?

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6km/h
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the average speed of a bicycle,an athlete and car are18km/h ,7m/s ,2km/min respectively.which of three is fastest and which is the slowest?

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i mean I am sorry there is correction
BICYCLE = 5m/s
and CAR = 33.3m/s
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CAR is fastest &
BICYCLE is slowest
car=5m/s
athlete=7m/s
car=33.3m/s
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Give an example each for velocity and average velocity. Please don't explain the term or formula. I want examples

IF ANSWER IS WRIGHT SO, DONT SAY THANKS
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FIND THE AVERAGE VELOCITY OF A MOTER BIKE IF IT MOVES WITH VELOCITY 50KM/HR FOR 10 MIN THEN 40 KM/HR FOR TIME 20 MIN
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What is the difference between velocity and average velocity?

Please answer my question! I want someone to find it out.
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Answers:

 Velocity refers to the rate of change of distance with respect to time. It is a vector quantity, which means that it has both  a direction and a magnitude.
 Average velocity refers to the average total displacement over the time of travel. It is calculated by determining the average of inital and final velocities.
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what is the reason that solution of pottsium permanganate remains coloured even after large number of dilutions

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The solution of Pottasium permagnate remains coloured after dilution because the size of particles are very small and remain present in solutins after dilution.
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Matter is made up of particles. How?

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All the matters are made up of very tiny particles that shows interparticlular attraction.
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can u help me in understating thechapters which are on the basis of motion

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The 3 laws r very imp.then all definitions too..read text and practice qns
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what is matter ?

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Ans. Matter is anything, such as a solid, liquid or gas, that has weight (mass) and occupies space.
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A submarine emits a sonar pulse which return from an underwater cliff in 1.2 seconds if the speed of sound in a sea water is 1530 metre per second how far is the Cliff from the submarines

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Time =1.2second
Distance = ?
Speed = distance travelled /time taken
1530=distance/1.2
Distance = 1530×1.2 = 1836m
So1836m far cliff from submarine
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In a factory 4 bulb 100 watt each and 5 fans of 110 what is operate for 12 hours daily. calculate the unit of electricity consumed also find the total expenditure of 1 unit cost rupees 2.50

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Ans. Power of 4 bulbs of 100 Watt = {tex}4\times 100 = 400W = 0.4KW{/tex}
Power of 5 Fans of 110 Watt = {tex}5\times 110 = 550W = 0.55KW{/tex}
Total Power = 0.4 + 0.55 = 0.95KW
Time = 12hours
Electricity Consumed = {tex}Power \times time{/tex}
=> {tex}0.95\times 12 = 11.40 \space KWh{/tex}
Rate of Unit = 2.50 Rs.
Total Expenditure = {tex}11.40 \times 2.50 = 28.50 Rs{/tex}
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Loaded test tube placed pure milk sinks to a certain mark m and now some water is mixed with the milk will a test tube sink more or less explain

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Loaded Test tube (Lactometer) will sink more as the desnity of milk is decreased due to addition of water.
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A force of 300 Newton acts on a surface of area 10 centimetres square calculate thrust and pressure calculate the change in pressure is the area increase to 50 centimetre square

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Force = 300N
Area of square = 10 cm2 = 0.01 m^{2}
Thrust = Force/ area = 300N/ 0.01 m^{2 }= 30000 Pa.
New area= 50 cm2 = 0.25 m2
new pressure = 300/0.25 = 1200 Pa.
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The mass of a iron cube having an edge length 1.8 centimetre is 70 gram find density

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Ans. Edge of iron cube = 1.8 cm
Volume of iron cube V = {tex}1.8\times 1.8\times 1.8 = 5.832cm^3{/tex}
Mass of iron cubd m = 70g
{tex}Density \space \rho = {mass \over volume } ={ 70\over 5.832}{/tex}= 12.0027g/cm^{3}
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How do you determine the maximum number of electron that can be accommodated in particular cell of an atom

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By the formula of (2n²)
Like for the k shell = we know that k shell is the first shell of atom so by using above formula we easily calculate the maximum number of electon accomondate in a shell where n is the no. of shell
(2n²)= 2×(1)²=4
So k shell have maximum four electrons
So by using this formula we find no. Of electrons in L shell M shell and so on.....
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Classify the disease into categories on the basis of period of their appearance and explain in brief. give two example of disease of each category.

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Two categaries of disease on the basis of period of their appearance are
a. Acute disease
b. Chronic disease.
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define avogadro constant

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Avogardo number is the a constant that represpents 6.22 x 10^{23} particles. it is the number of particles present in one mole of any element or molecule.
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What is gravitation

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Gravitation is the force by which earth attracts all the objects towards its centre.
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what are ions?

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Charge particles are called ions. Positevely charged ions are called cation and negatively charged ions are called anion.
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any four characterstics of the frog?

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 Frog is an amphibian.
 It is cold blooded animal.
 It can live in water as well as land.
 body is soft and slippery.
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what is atomic no.?

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The number of protons present in the nucleus of an atom is called atomic number.
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what is nomenclature?

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The process of naming scientifically following rules is balled nomenclature. In biology it is called as binomial nomenclature.
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what is the symbol,atomic no. and atomic mass of sodium?

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symbol Na
atomic no 11
atomic mass 23
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