# Search results

1. ### Undetermined coefficient (y'' + 4y) = (x^2) +2

i have attached the working in the picture uploaded above
2. ### Center of gravity vs center of buoyancy

can you show me where is the r for the FB to generate restoring moment and overturning moment in the diagram ? so that i can understand better what you said
3. ### Undetermined coefficient (y'' + 4y) = (x^2) +2

i have redo the question , i got Acos2x + Bsin2x +0.25x^2 + 3/2 , but the ans given is Acos2x + Bsin2x +0.25x^2 +3/8
4. ### Undetermined coefficient (y'' + 4y) = (x^2) +2

then , what is the correct yp ? i choose my initial yp = cX^2 + Dx + E , nut i found that the term E is similar to the A , so i multiply the initial yp with x , to get my new yp
5. ### Undetermined coefficient (y'' + 4y) = (x^2) +2

Homework Statement i gt stucked here ... how to continue ? what's wrong with my working ? i found 2 values for D , whcih is wrong Homework Equations The Attempt at a Solution
6. ### Center of gravity vs center of buoyancy

Homework Statement when the ship is tilted more , the ship will become inclined more ( bigger portion of right hand side part of the ship will be submerged in water ) . this caused the center of buoyancy to be located more to the right , this cause the B is very far from the G . The ship will...
7. ### Center of gravity vs center of buoyancy

Homework Statement why the floating body still stable when G ( center of gravity ) is above the B ( center of buoyancy)? Homework Equations The Attempt at a Solution in my opinion , the statement is worng , because when G is above B , G has the tendency to move downward , causing the object...
8. ### Direction of resultant force

isnt that the the resultant force on blade and forecs of steam of water are of same magnitude and same direction ?
9. ### Direction of resultant force

the horizontal component of force should be -1.272 N + 2.54 = 1.27N N to the right, whereas the direction and magnitude of vertical force is the same ? then , the direction of resultant of force should be upwards just like the diagram below?
10. ### Pressure at points

z represent the difference in height between 2 points
11. ### Formula of forces

do u mean since the width is unknown and constant through out the whole object , so we can take it out and leave the ans (Fx) is Force per unit width>
12. ### Pressure at points

how to relate it to the P1 ? why not P1 = P2 , which is ρg(h1 +h2 +h3) ?
13. ### Formula of forces

ok , i can understand the red part of the equation (9810)(2.1)(4.2)- 9810(0.35)(0.7) -Fx = 1000(5.88)(8.4-1.401) , but 1000(5.88)(8.4-1.401) is force , am i right ? it's not force per unit width... they are not having the same unit...how cvan they be equqal to each other?
14. ### Direction of resultant force

Homework Statement why the resultant force on blade is acted downwards (toward A)? why shouldn't it be slanted upwards ? since the horizontal component of the force acted 2.12kN to the left , and 0.735kN upwards , we would get the resultant force acting slanted upwards , right ? Homework...
15. ### Pressure at points

it should be P/ y + z + (v^2) /.2g , where v = velocity , y = ρg
16. ### Pressure at points

P +z + (v^2) /.2g , wher v = velocity
17. ### Formula of forces

Homework Statement what is the 2.1 and 0.35 refers to in the equation of (9810)(2.1)(4.2)- 9810(0.35)(0.7) -Fx = 1000(5.88)(8.4-1.401) ?? is it the width ? but , the width is not given ? Homework Equations The Attempt at a Solution
18. ### Pressure at points

maybe there are some points that i have left out , can you point out please?
19. ### Pressure at points

can you explain how to apply the Beroulli's pronciple so that the P1 = pg(h1 +h2) ? but not P1 = pg(h1 +h2+h3) ?
20. ### Pressure at points

can you explain further?
21. ### Pressure at points

Homework Statement isn't that p1 and [2 at the same point ? why shouldn't the P1 = P2 , which is ρg(h1 +h2 +h3) ? Homework Equations The Attempt at a Solution
22. ### Coefficient of discharge

Homework Statement why the author consider the coefficient of discharge as the z here ? what is exactly coefficient of discharge? Homework Equations The Attempt at a Solution
23. ### Min force to open the water gate

Homework Statement why Fr(Lp) = FB / 2 ? can someone help to explain ? Homework Equations The Attempt at a Solution shouldn't it be 2FB = Fr(Lp) ? since FB act on 2 sides of the gate ...[/B]
24. ### Formula of object immersed in water

according to 3-18 , i would get P (yc^2) A instead of P (yc) A ... am i correct ?
25. ### Density of body and density of liquid

Homework Statement how can the average density of the body equal to the density of fluid(2nd photo) ? the object is not completely submerged in the liquid , so the density of object should be lower , right ? Homework Equations The Attempt at a Solution
26. ### Kinematic viscosity depends on pressure

so , which is correct ? kinematic viscosity or dynamic viscosity depends on pressure?
27. ### Formula of object immersed in water

Homework Statement why the y ſ P dA will equal to P yc A ? why not P (yc^2) A ? since yc = ſ y dA / A Homework Equations The Attempt at a Solution
28. ### Kinematic viscosity depends on pressure

Homework Statement I was told that kinematic viscosity depends on pressure , but not dynamic viscosity Homework Equations The Attempt at a Solution in my opinion, the dynamic viscosity depends on pressure , since it's formula is μ = tau / (du/dy) , where tau is the stress . and stress can...
29. ### Restoring moment

Homework Statement why the restoring moment in diagram 3-48 must be in anti-clockwise direction ? can't be in clockwise direction ? pls refer to the last photo ( i sketched it) , if the B' is located on the left of the G , teh restoring moment is clockwise, right ? Homework Equations The...
30. ### Weight of fluid block

Homework Statement why the formula of weight of fluid block is given by the formula of ρg[ (R^2) - pi(R^2) ] 1? what does the 1m mean here ? shouldn't it = ρg (pi) (R^2) h ? 2. Homework Equations The Attempt at a Solution
31. ### Forces on submerged surface

Homework Statement i don't understand the statement 1 and 2 , can someone help to explain ? for 1 , does the author mean Fh= Fv ?? for 2 , does the author mean Fv = Fh + W ? but in statement 1 , Fh already = Fv Homework Equations The Attempt at a Solution
32. ### Curvature effect can be neglected

why ? i still can't understand
33. ### Prism volume

how can The volume of the pressure prism is equal to the magnitude of the force exerted by a hydrostatic pressure P applied over an area A ?
34. ### Curvature effect can be neglected

when R is big relative to l , we can only say that the two circle 'combined together' , right ? how can the curvature be neglected?
35. ### Curvature effect can be neglected

what do you mean ? can you explain further?
36. ### Prism volume

Homework Statement why the formula of volume is given by integral of P and dA , the integral of P and dA would yield Force , right ? Homework Equations The Attempt at a Solution
37. ### Support of fluid

i am asking about , if no wall is present , how can it not eliminate stress?
38. ### Formula of viscosity

i think it is wrong
39. ### Formula of viscosity

i don't agree with the formula mass/ (length x area)
40. ### Formula of viscosity

Homework Statement why the alternative formula of viscosity not = (mass x length ) / ( time x area) ? for force x time , we would get (mass x length ) / time ... Homework Equations The Attempt at a Solution
41. ### Curvature effect can be neglected

can you explain in detail by giving analogy (is arrow represent ℓ ) ?
42. ### Support of fluid

Homework Statement why the fluid need the wall to eliminate the shear stress? Homework Equations The Attempt at a Solution is it because if there is no wall to support teh fluid , the fluid would move continously , resulting the shear stress act on water?
43. ### Curvature effect can be neglected

Homework Statement why when ℓ / R ≪ 1 , the curvature effect can be neglected ?? Homework Equations The Attempt at a Solution no matter how small or how big is R , it is strill considered as curvature , right ??
44. ### Force of bubble

i have one more question here . I was also told that the pressure at the concave side of the bubbles is higher ... why is it so ? is it because of the circumference of the pressure at the concave side is higher?
45. ### Force of bubble

Homework Statement why the force of bubble is given by the formula of 2(2 pi R ) σs ? why not (2 pi R ) σs + (2 pi R+ ΔR) σs ? Since the radius of th outer circumfernece and inner circumference are the different ? Homework Equations The Attempt at a Solution
46. ### Water in hose

ok , so is my statement in post #5 correct ?
47. ### Force in pipe

what do yo you mean ? we want to find the resultant force , right ? So , the correct approach would be 12cos60 + 12 , right ? since they are both directed to the right
48. ### Force in pipe

so , the notes is wrong ? the velocity should add up ?
49. ### Force in pipe

I want to ask A and the inlet first
50. ### Force in pipe

velocity along the x direction . (circled part)