Students and Teachers Forum

1. How does nitrogen oxide destroy ozone layer? Write with chemical equation.

Nitrous oxide is also a heat-trapping greenhouse gas in the league of methane or carbon dioxide, so regulating it would also be good for the climate, he says. Nitrous oxide (N2O) is produced naturally when nitrogen in soil or water is eaten by .....

2. If the volume and the radius of a cylinder are 1078 cubic and 7cm respectively, find the height of the cylinder.

.....

3. If f(x) = 1/x, x ≠ 0 prove that: fof -1 = f -1of.
 

Here,  f(x) = y = 1/x To find f -1(x), we need to interchange role of x & y So,  x = 1/y  or, y = 1/x =  f -1(x), Now,  fof -1 = f{ f -1(x)}          = .....

4. Rule regarding the salary of the new employee in a company is initial salary of  Rs.9000 and after eight six months there is an increment of Rs.500 upto 4 years. Find the monthly salary of an employee after 4 years .

Here,  Initial salary of an employee = Rs. 9000 After each six month there is an increment of Rs. 500 After one year there is an increment of Rs.1000 After 4 years there will be an increment of = 4 ⨉ Rs. 1000 = Rs. 4000 Therefore, .....

5. If fx= 2x+54 and gx= 4x+75 then show that fogx+ 920=gofx.

Given, fx= 2x+54 and gx= 4x+75 fog(x) = f[g(x)]           =24x+75+ 54 =8x+145+ 54 =8x+14+2554 = 8x+395 × 14 fog(x) =  8x+3920 ..................................[1] Now, gof(x)= 42x+54+ .....

6. If f (x )= 4x -1 and fog (x ) = 3 x - 2 find g-1(2).

Here, given  f (x )= 4x -1 fog (x ) = 3x - 2 Let, g(x) = a Then, fog(x) = 4a - 1 3x - 2 = 4a - 1 3x - 2 +1 = 4a or, a = (3x - 1)/4 = g(x) or, g(x) = (3x - 1)/4 Let, y =  (3x - 1)/4 Interchanging the value of 'x' .....

7. The charge of ISD call for Canada from Pokhara is Rs.200 for the first minute and Rs.20 for every additional 15 seconds . If a man made the telephone call and paid Rs.600 for the bill, how long did he make the call?

.....

8. Find the total surface area of the figure.

.....

9. In the given figure, if PA = (1/4) PQ, prove that vector a = 1/4(3 vector p + vector q)

PQ = PB + BQ = - p + q  .....(i)      [ Using triangle rule of vector addition.] In triangle BAP, PA = PB + BA = - p + a    ...(ii)      [ Using triangle rule of vector addition.] We have .....

10. If the sum of radius and height of a cylinder is 10cm and the circumference of its base is 308cm, find the total surface area of the cylinder.

.....

11. The total surface area of a solid hemisphere is 1848 sq.cm. Find its radius.

.....

12. The diametre of the base of a cylinder is 20cm and its height is 6.3. Find its curved surface area.

.....

13. If height and radius of a cylindrical wood are equal and its curved surface area is 308cm2, find the hight.

.....

14. If the line x cos α + y sin α = p passes through the point of intersection of the lines x = 2 and y = 3 is parallel to the lines √3 x + y = 2, find the values of acute angle α and p.

Here,  Slope of x cos α + y sin α = p is  m1 = -  coefficient of x / coeff.of y = - cosα/sinα =  - cot α  Again, slope of line √3 x + y = 2 is  m2 = .....

15. Given
principal (p)=40000
rate(r)=3%
time(t)= 3 months
find compound interest (c.I)=?

Here, given Principal (P)= Rs.40000 Rate(R)=3% Time(T)= 3 months = 3/12 = 1/4 years. Compound interest (C.I)=? We have  formula, C.I. = P[ (1 + R ∕ 100)T -1 ]        = Rs.40000[ ( 1 + 3/100)1/4 - .....

16. Mohan lent altoghter Rs.6600 to Ram and Shyam for 2 years. Ram agrees to pay simple interest at 15% p.a. & Shyam agrees to pay compound interest at the same rate. If Ram paid Rs.112.50 more than Shyam as the interest, how mush did he lend to each?

Here,  Rate = R = 15% Time = T = 2years For Ram, P = x (say) SI = PTR/100 = x ⨯ 2  ⨯ 15/100 = 3x/10 For Shyam,  P = 6600 - x CI = P[ ( 1 + R/100)T - 1]       = (6600 - x)[ ( 1 + .....

17. The volume of the given solid is 1536cm3, find the height of the solid.

Here,  Length of side of base = b = 12cm Total height = h1 + h2 = a cm Volueme of solid = 1536cm3 or, volume of upper pyramid + volume of lower pyramid = 1536 or, 1/3 ⨯b2h1 + 1/3 ⨯b2h2 = 1536 or, .....

18. Prove that: 2 / (a1/4 - 1) - a1/4 / (a1/2 + 1) - 1/ (a1/4 + 1) - 3 / (a1/2 - 1) = 2a1/4 / (a - 1) .

Here,  LHS = 2 / (a1/4 - 1) - a1/4 / (a1/2 + 1) - 1/ (a1/4 + 1) - 3 / (a1/2 - 1) Arranging we get, = 2 / (a1/4 - 1) - 1/ (a1/4 + 1) - a1/4 / (a1/2 + 1) - 3 / (a1/2 - 1) = .....

19. The perimeter of a rectangular ground is 100m. When its side is reduced then new length and breadth are 5/6 & 75% of the previous length & breadth. If new perimeter of the ground is 80m, what was the length and breadth of the ground in the beginning? Find it?

Let l and b be the initial length and breadth of rectangular ground. From the first case,  2(l + b) = 100                      [ Since, P = 2(l + b).] or, l = 50 - .....

20. The area of a rectangular ground is 40m2. If the length & breadth are (x + 3) & (x - 3)m, find its perimeter.

Here,  Length = l = x + 3 Breadth = b = x - 3 Area = 40m2. We know,  Area of rectangular field = l ⨯ b or, (x + 3)(x -3) = 40 or, x2 = 49 or, x = 7       [ ignore the -ve value.] Find l = x + 3 and b= x .....

21. By using more than type frequency curve, find the classes of lower quartile, middle quartile and upper quartile.

Here,  Total frequency = N = 22. Positon of 1st quartile = 3N/4th item = 3 ⨯ 22/4 = 16.5th item  [Since, for more than cf, position of  Q1 & Q3 are reversed.] From the graph, corresponding class  .....

22. वक्य बनौ

प्रश्न स्पष्ट लेख्नुहोला .....

23. What is translator program?

The different types of translator are as follows: Compiler is a translator which is used to convert programs in high-level language to low-level language. It translates the entire program and also reports the errors in source program encountered .....

24. निबन्ध लेख:
गाँउले जीवन

स्वच्छ अनि सफा वातावरणमा बिताएको जीवन गाँउले जीवन मलाई एकदमै मन पर्छ । गाँउको प्रत्यक .....

25. भाव विस्तार गर: नेपाल प्राकृतिक विविधताले भरिपूर्ण विश्वको सुन्दर मुलुक हो।

नेपाल बहु भौगोलिक विशेषता भएको मुलुक हो । त्यसैले नेपाललाई विविधताको बँगैचा भन्न सकिन्छ । .....

26. If  g = { x, 5x - k} and g - 1(2) = 4/5, find the value of k.

Here,  g(x) = 5x - k. Let y = 5x - k Under the g-1, role of x & y are interchanged. So,  x= = 5y - k or, y = (x + k) /5 = g-1(x) Again,  g-1(2) = 4/5 or, (2 + k)/5 = 4/5 Now solve & get the value of .....

27. If  function f (x) = (2x + 5)/(x + 2), find f -1(x) and show that ff -1(x) is an identity function.

Here,  y = f(x) = (2x + 5)/(x + 2) Under the f -1, role of x & y are interchanged, So, x =  (2y + 5)/(y + 2) or, 2xy + 2x = 2y + 5 or, 2xy - 2y = 5 - 2x or, y(2x - 2) = 5x - 2 or, y = (5x - 2)/(2x - 2) Thus, .....

28. If f(x)= 3x + 5 and fog(x) = (7x - 1)/3, find g(x).

Here,  fog(x) = (7x - 1)/3 or, f{g(x)} = (7x - 1)/3 or, 3g(x) + 5 = (7x - 1)/3     [ Since, f(x)= 3x + 5.] Now simplify and find .....

29. हामी=? कर्मिशल=? हुनुपर्छ =? कर्ममा=? समाज=? शब्दवर्ग छुट्याउनु होस।

प्रश्न स्पष्ट लेखिदिनुहोला .....

30. १९. तलको विवरणका आधारमा छोटो जीवनी लेखेर शिक्षकलाई देखाऊ
नामः त्रैलोक्यनाथ पोखरेल
जन्मः वि.सं. १९९० फागुन, धनकुटा
बाल्य जीवनः सामान्य परिवारको भएकाले दुःख सुखमा बितेको
विशेष घटनाः वि.सं. १९९२ सालमा विफरको महामारी फैलिएको, त्यही महामारीले आँखाको हेर्ने शक्ति नष्ट भएको
मिहिनेत र साधनाः अरूले भनेको सुनेर पाठ कण्ठ पार्ने बानी, यही क्रममा वि.सं. २०२१ सालमा आफूले उत्तर भन्ने र सहयोगीले लेखिदिने गरेर एसएलसी परीक्षा उत्तीर्ण, क्रमशः यसरी नै पढेर र जाँच दिएर आइए, बिए र एमए उत्तीर्ण, एमए उत्तीर्ण भएको साल वि.सं. २०२९
वि.सं. २०३० देखि २०५८ सम्म त्रिचन्द्र कलेजमा प्राध्यापन
निधनः वि.सं. २०५८ जेष्ठ १९ गते

त्रैलोक्यनाथ पोखरेल वि.सं. १९९० फागुन महिनामा धनकुटामा जन्मिएका थिए । पारिवारिक स्थिति .....

31. पेज न ,४४ को प्र,१९

प्रश्न नै लेखेर पठाउनुहोस् न ल .....

32. Write the essay on " importance of library" 400 words.(10 marks question)

                                                  Importance of Library  A library is a treasure-house of knowledge. A .....

33. कोइलिको वसन्त रितुमा आफ्नो दिन कसरी बित्छ। १० मार्क्सको प्रस्न हो लामो उत्तर दिनु होला।

वसन्त ॠतुमा  हरियाली पालुवा पलाउने र मगमग वनफूल फुलेर वातावरणा नै  मनोरम .....

34. सुम्म्रय ओन थिस तोपिच
questionimage

साथी, प्रश्नले के भनेको हो, मलाई बुझाइदिनुहोस् न ल .....

35. What is brittleness?

Brittleness is a property of metals which states that they do not deform under load but suddenly break. It is basically the tendency of metals or a material to fracture or break even upon the application of small impact, force or .....

36. 'कुमाल' शब्द हो। (पर्यायवाची, अनेकार्थी, लघुतावाची)

कुमाल अनेकार्थक शब्द हो .....

37. Which method of separation of mixture is suitable to separate the following mixture.
a) platelets from blood
b) water from salt solution

a) Cenrtifugation . b) .....

38. Why is local government needed? What obstacles can be faced in the obsence of local government?

In the absence of local governments, we may face the following obstacles: - The development of local levels will be lagging behind. - Unity in diversity may not be maintained. - No proper utilization of resources available at local levels - .....

39. No one in the world is useless. Justify

 No one in the world is useless means that every person has got the huge significance of relevance in any way who has something to do in the world. Even if personalities are different and circumstances are varied, everybody person is important .....

40. Everything you see or do will relate to your self image. Explain

 Self-image is about how you see yourself and how you believe others see you. Everything we do as a human being is what makes known to others. Whatever we perceive the thing either positively or negatively makes us who we are and what we are .....

41. The true worth of people lies within them. Justify

It is obvious that the value that a person has something to do for his or her own personality is what their character is reflected upon. Whatever the capability that they possess, it is reflected in their activities, the way they talk, .....

42. From a cylinder having height 20cm, a hemisphere of equal radius is removed out. Find the radius of the cylinder if the curved surface area of remaining part is 1188cm2. 

Here,  Let r be the common radius. CSA = CSA of hemisphere + CSA of cylinder or, 1188 = 2πr2 + 2πrh , here, h= 20cm. or, 1188 = 2⨯22/7 ( r2 + 20r) or,189 = r2 + 20r or, r2 + 20r - 189 = 0 Factorize and find .....

43.  We know that gravitational force is directly proportional to the product of masses and inversely proportional to the square of distance between their centre. Now, answer the following question.

a) If the mass of body A is double and that of body B is tripled keeping the distance between them constant, what change in gravitaional force between the bodies will be experienced?

b) By keeping the masses constant if the distaqnce between them is decreased by 3 times, what change in gravitaitonal force will be found?

Let m1 and m2 be any two masses separated by the distance 'd'. If F be the gravitational force between them, than according to Newton's law of gravitation, F = (Gm1m2)/d2 .......i) Let  m1' and .....

44. In the figure, D, E and F are points on BC, AB and AC resp. such that △ABD = △ EBC, If DF and CE intersect at G, prove that △ EFG = △ CDG

Join E and D. Here, △ABD = △ EBC From this you can show △AED = △ EDC. So, ED//AC. Now, you can write △EDF = △ EDC. Use this relation and show △EFG = △ .....

45. Find the value of angle UOR and angle UKA.

 

Here,  ∡UOR = 2 ∡UAR        [ Central angle is double of inscribed angle on same arc UR.] So, ∡UOR = 60o. In triangle OUR, Find ∡URO. Then, ∡URA = 70o + ∡URO =............Find .....

46. AB is diameter,arc AC =arc CD. find the value of x and y.

 

Here,  ∡COD = ∡AOC = 60o    [ Equal arc makes equal angle.] So, ∡ABC = 1/2 of ∡AOC = 30o  [ Inscribed angle is half of central on same arc.] ∡OCB = ∡OBC = 30o   [ OB = .....

47. Describe the role of Lumbini to popularize Nepal in the whole world.

We know that Lumbini is one of the national heritage of the country. It is the identity of our country and its people. Lumbini was listed in the UNESCO World Heritage Sites in the year 1997 AD. It helps us to be introduced to the international .....

48. Agriculture is at the heart of the Nepalese people. Explain.

Similarly, the Terai region of Nepal is known as the granary of Nepal. It is composed of fertile soil which is suitable for agricultural activities. Likewise, the climatic condition of Nepal is suitable for agricultural activities. And if .....

49. What are the name of reptiles

List of reptiles are: 1. Snake 2. Crocodile 3. Lizard 4. .....

50. What do you mean by women's right?

- Right to work - Right to fair wages or equal pay - Right to serve in the military - Right to have marital or parental rights, .....