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Question Number 10289 Answers: 1 Comments: 0

((9−x^2 )/x)+3=((x−3)/3)⇒Σx=?

$$\frac{\mathrm{9}−\mathrm{x}^{\mathrm{2}} }{\mathrm{x}}+\mathrm{3}=\frac{\mathrm{x}−\mathrm{3}}{\mathrm{3}}\Rightarrow\Sigma\mathrm{x}=? \\ $$$$ \\ $$

Question Number 10286 Answers: 1 Comments: 0

2000g of water at 100°C is poured into a copper calorimeter 150g of water at 10°C. The temperature of the mixture is 45°C. Calculate the thermal capaity of tbe vessel. specific heat capacity of copper = 400 specific heat capacity of water = 4200

$$\mathrm{2000g}\:\mathrm{of}\:\mathrm{water}\:\mathrm{at}\:\mathrm{100}°\mathrm{C}\:\mathrm{is}\:\mathrm{poured}\:\mathrm{into}\:\mathrm{a}\: \\ $$$$\mathrm{copper}\:\mathrm{calorimeter}\:\mathrm{150g}\:\mathrm{of}\:\mathrm{water}\:\mathrm{at}\:\mathrm{10}°\mathrm{C}. \\ $$$$\mathrm{The}\:\mathrm{temperature}\:\mathrm{of}\:\mathrm{the}\:\mathrm{mixture}\:\mathrm{is}\:\mathrm{45}°\mathrm{C}. \\ $$$$\mathrm{Calculate}\:\mathrm{the}\:\mathrm{thermal}\:\mathrm{capaity}\:\mathrm{of}\:\mathrm{tbe}\:\mathrm{vessel}. \\ $$$$\mathrm{specific}\:\mathrm{heat}\:\mathrm{capacity}\:\mathrm{of}\:\mathrm{copper}\:=\:\mathrm{400} \\ $$$$\mathrm{specific}\:\mathrm{heat}\:\mathrm{capacity}\:\mathrm{of}\:\mathrm{water}\:=\:\mathrm{4200} \\ $$

Question Number 10282 Answers: 1 Comments: 1

210 cm^3 of Nitrogen at a pressure of 400 mmHg and 100 cm^3 of carbon(iv)oxide at a pressure of 350 mmHg were introduce into a 200 cm^3 vessel. what is the total pressure in the vessel.

$$\mathrm{210}\:\mathrm{cm}^{\mathrm{3}} \:\mathrm{of}\:\mathrm{Nitrogen}\:\mathrm{at}\:\mathrm{a}\:\mathrm{pressure}\:\mathrm{of}\:\mathrm{400}\:\mathrm{mmHg} \\ $$$$\mathrm{and}\:\mathrm{100}\:\mathrm{cm}^{\mathrm{3}} \:\mathrm{of}\:\mathrm{carbon}\left(\mathrm{iv}\right)\mathrm{oxide}\:\mathrm{at}\:\mathrm{a}\:\mathrm{pressure}\: \\ $$$$\mathrm{of}\:\mathrm{350}\:\mathrm{mmHg}\:\mathrm{were}\:\mathrm{introduce}\:\mathrm{into}\:\mathrm{a}\:\mathrm{200}\:\mathrm{cm}^{\mathrm{3}} \\ $$$$\mathrm{vessel}.\:\mathrm{what}\:\mathrm{is}\:\mathrm{the}\:\mathrm{total}\:\mathrm{pressure}\:\mathrm{in}\:\mathrm{the}\:\mathrm{vessel}. \\ $$

Question Number 10277 Answers: 2 Comments: 0

How can kerosine be heated ???. please give reasons.

$$\mathrm{How}\:\mathrm{can}\:\mathrm{kerosine}\:\mathrm{be}\:\mathrm{heated}\:???.\: \\ $$$$\mathrm{please}\:\mathrm{give}\:\mathrm{reasons}. \\ $$

Question Number 10268 Answers: 2 Comments: 0

Question Number 10265 Answers: 1 Comments: 0

From the top of a 100 m high building, a man observes the top of a tree at an angle of depression 30°. If the tree is 50 m tall, the angle of depression of the foot of the tree is viewed by the man is ?

$$\mathrm{From}\:\mathrm{the}\:\mathrm{top}\:\mathrm{of}\:\mathrm{a}\:\mathrm{100}\:\mathrm{m}\:\mathrm{high}\:\mathrm{building},\:\mathrm{a}\:\mathrm{man} \\ $$$$\mathrm{observes}\:\mathrm{the}\:\mathrm{top}\:\mathrm{of}\:\mathrm{a}\:\mathrm{tree}\:\mathrm{at}\:\mathrm{an}\:\mathrm{angle}\:\mathrm{of} \\ $$$$\mathrm{depression}\:\mathrm{30}°.\:\mathrm{If}\:\mathrm{the}\:\mathrm{tree}\:\mathrm{is}\:\mathrm{50}\:\mathrm{m}\:\mathrm{tall},\:\mathrm{the} \\ $$$$\mathrm{angle}\:\mathrm{of}\:\mathrm{depression}\:\mathrm{of}\:\mathrm{the}\:\mathrm{foot}\:\mathrm{of}\:\mathrm{the}\:\mathrm{tree}\:\mathrm{is} \\ $$$$\mathrm{viewed}\:\mathrm{by}\:\mathrm{the}\:\mathrm{man}\:\mathrm{is}\:? \\ $$

Question Number 10250 Answers: 1 Comments: 1

Question Number 10245 Answers: 1 Comments: 0

prove that determinant ((1,1,1),(x,y,z),(x^2 ,y^2 ,z^2 ))=(x−y)(y−z)(z−y)

$$\mathrm{prove}\:\mathrm{that}\: \\ $$$$\begin{vmatrix}{\mathrm{1}}&{\mathrm{1}}&{\mathrm{1}}\\{\mathrm{x}}&{\mathrm{y}}&{\mathrm{z}}\\{\mathrm{x}^{\mathrm{2}} }&{\mathrm{y}^{\mathrm{2}} }&{\mathrm{z}^{\mathrm{2}} }\end{vmatrix}=\left(\mathrm{x}−\mathrm{y}\right)\left(\mathrm{y}−\mathrm{z}\right)\left(\mathrm{z}−\mathrm{y}\right) \\ $$

Question Number 10248 Answers: 2 Comments: 0

solve the value of x logx^2 =(x/(25))

$$\mathrm{solve}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\:\mathrm{x} \\ $$$$\:\:\:\mathrm{logx}^{\mathrm{2}} =\frac{\mathrm{x}}{\mathrm{25}} \\ $$

Question Number 10243 Answers: 0 Comments: 0

solve the eqution determinant (((x−3),1,(−1)),((−7),(x+5),(−1)),((−6),6,(x−1)))=0

$$\mathrm{solve}\:\mathrm{the}\:\mathrm{eqution} \\ $$$$\:\:\:\:\:\begin{vmatrix}{\mathrm{x}−\mathrm{3}}&{\mathrm{1}}&{−\mathrm{1}}\\{−\mathrm{7}}&{\mathrm{x}+\mathrm{5}}&{−\mathrm{1}}\\{−\mathrm{6}}&{\mathrm{6}}&{\mathrm{x}−\mathrm{1}}\end{vmatrix}=\mathrm{0} \\ $$$$ \\ $$

Question Number 10242 Answers: 2 Comments: 1

f(x)=((sin(x+n))/(cos(x−n))) if f(x)=1, n=??

$${f}\left({x}\right)=\frac{\mathrm{sin}\left({x}+{n}\right)}{\mathrm{cos}\left({x}−{n}\right)} \\ $$$$\mathrm{if}\:{f}\left({x}\right)=\mathrm{1},\:\:{n}=?? \\ $$

Question Number 10241 Answers: 0 Comments: 1

∫_a ^( a+δ) ((sin(x))/(cos(x+δ)))dx = ???

$$\int_{{a}} ^{\:{a}+\delta} \frac{\mathrm{sin}\left({x}\right)}{\mathrm{cos}\left({x}+\delta\right)}{dx}\:=\:??? \\ $$

Question Number 10237 Answers: 1 Comments: 0

(1) 4H_2 O (2) FeSO_4 + K_2 Cr_2 O_7 help in balancing ironically and atomically.

$$\left(\mathrm{1}\right)\:\mathrm{4H}_{\mathrm{2}} \mathrm{O}\:\: \\ $$$$\left(\mathrm{2}\right)\:\mathrm{FeSO}_{\mathrm{4}} \:+\:\mathrm{K}_{\mathrm{2}} \mathrm{Cr}_{\mathrm{2}} \mathrm{O}_{\mathrm{7}} \\ $$$$\mathrm{help}\:\mathrm{in}\:\mathrm{balancing}\:\mathrm{ironically}\:\mathrm{and}\:\mathrm{atomically}. \\ $$

Question Number 10236 Answers: 1 Comments: 0

An electron moves in a vacuum between two electrode having a p.d of 3000v, calculate the velocity acquired by the electon if the ratio of its charge to mass is 1.8×10^(11) Ckg^(−1)

$$\mathrm{An}\:\mathrm{electron}\:\mathrm{moves}\:\mathrm{in}\:\mathrm{a}\:\mathrm{vacuum}\:\mathrm{between} \\ $$$$\mathrm{two}\:\mathrm{electrode}\:\mathrm{having}\:\mathrm{a}\:\mathrm{p}.\mathrm{d}\:\mathrm{of}\:\mathrm{3000v},\:\mathrm{calculate} \\ $$$$\mathrm{the}\:\mathrm{velocity}\:\mathrm{acquired}\:\mathrm{by}\:\mathrm{the}\:\mathrm{electon}\:\mathrm{if}\:\mathrm{the}\:\mathrm{ratio} \\ $$$$\mathrm{of}\:\mathrm{its}\:\mathrm{charge}\:\mathrm{to}\:\mathrm{mass}\:\mathrm{is}\:\mathrm{1}.\mathrm{8}×\mathrm{10}^{\mathrm{11}} \mathrm{Ckg}^{−\mathrm{1}} \\ $$

Question Number 10232 Answers: 1 Comments: 0

x∈Z, A∈R A=^4 (√(3−∣x−4∣)) ⇒Σx=?

$$\mathrm{x}\in\mathrm{Z},\:\mathrm{A}\in\mathrm{R} \\ $$$$\mathrm{A}=^{\mathrm{4}} \sqrt{\mathrm{3}−\mid\mathrm{x}−\mathrm{4}\mid}\:\Rightarrow\Sigma\mathrm{x}=? \\ $$

Question Number 10228 Answers: 0 Comments: 4

B is the matrix ⌈ 3 1 −3⌉ ∣ 1 2a 1 ∣ ⌊ 0 2 a ⌋ i.find the value of a for which B is singular ii.determine whether or not ⌈x ⌉ ⌈ −3.5⌉ B ∣y ∣ = ∣ 5.5∣ has the ⌊ z ⌋ ⌊ 5 ⌋ solution for each of the value of obtai ned in (i) above

$$\:\:\:\:\:\:\:\:\mathrm{B}\:\mathrm{is}\:\mathrm{the}\:\mathrm{matrix}\: \\ $$$$\:\:\:\:\:\:\:\lceil\:\:\mathrm{3}\:\:\:\:\:\:\mathrm{1}\:\:−\mathrm{3}\rceil \\ $$$$\:\:\:\:\:\:\:\mid\:\:\mathrm{1}\:\:\:\:\:\:\mathrm{2a}\:\:\:\mathrm{1}\:\:\mid \\ $$$$\:\:\:\:\:\:\:\lfloor\:\:\mathrm{0}\:\:\:\:\:\:\:\mathrm{2}\:\:\:\:\mathrm{a}\:\rfloor \\ $$$$\:\mathrm{i}.\mathrm{find}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\:\mathrm{a}\:\mathrm{for}\:\mathrm{which}\:\mathrm{B}\:\mathrm{is}\: \\ $$$$\:\:\:\:\mathrm{singular} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\mathrm{ii}.\mathrm{determine}\:\mathrm{whether}\:\mathrm{or}\:\mathrm{not}\: \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\lceil\mathrm{x}\:\rceil\:\:\:\:\:\:\:\:\:\lceil\:−\mathrm{3}.\mathrm{5}\rceil \\ $$$$\:\:\:\mathrm{B}\:\:\:\:\:\:\:\:\mid\mathrm{y}\:\:\mid\:\:=\:\:\:\:\mid\:\:\:\:\:\:\mathrm{5}.\mathrm{5}\mid\:\:\mathrm{has}\:\mathrm{the}\: \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\lfloor\:\mathrm{z}\:\:\rfloor\:\:\:\:\:\:\:\:\lfloor\:\:\:\:\:\:\:\mathrm{5}\:\:\rfloor \\ $$$$\mathrm{solution}\:\mathrm{for}\:\mathrm{each}\:\mathrm{of}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\:\mathrm{obtai} \\ $$$$\mathrm{ned}\:\mathrm{in}\:\left(\mathrm{i}\right)\:\mathrm{above} \\ $$

Question Number 10227 Answers: 1 Comments: 0

An aeroplane leaves a port P(51°S, 29°E) and after flying 7597 km due north it reached another port R. calculate the. (i) Latitude of R correct to the nearest degree (ii) Radius of parallel of latitude through R to the nearest whole number.

$$\mathrm{An}\:\mathrm{aeroplane}\:\mathrm{leaves}\:\mathrm{a}\:\mathrm{port}\:\mathrm{P}\left(\mathrm{51}°\mathrm{S},\:\:\mathrm{29}°\mathrm{E}\right)\:\mathrm{and} \\ $$$$\mathrm{after}\:\mathrm{flying}\:\mathrm{7597}\:\mathrm{km}\:\mathrm{due}\:\mathrm{north}\:\mathrm{it}\:\mathrm{reached}\: \\ $$$$\mathrm{another}\:\mathrm{port}\:\mathrm{R}.\:\mathrm{calculate}\:\mathrm{the}. \\ $$$$\left(\mathrm{i}\right)\:\mathrm{Latitude}\:\mathrm{of}\:\mathrm{R}\:\mathrm{correct}\:\mathrm{to}\:\mathrm{the}\:\mathrm{nearest}\:\mathrm{degree} \\ $$$$\left(\mathrm{ii}\right)\:\mathrm{Radius}\:\mathrm{of}\:\mathrm{parallel}\:\mathrm{of}\:\mathrm{latitude}\:\mathrm{through}\:\mathrm{R} \\ $$$$\mathrm{to}\:\mathrm{the}\:\mathrm{nearest}\:\mathrm{whole}\:\mathrm{number}. \\ $$

Question Number 10223 Answers: 3 Comments: 0