Biology; Chemistry; Physics: Post your doubts here!

[convent2012]

Pretty uncommon question Is it from Q/P?? which year then?

i got from an old work sheet . donot know the past paper number but i think its might be 4rm some book !

 

[lisahamed]

two rays, starting from M, diverging a little, striking the mirror, then reflected till P. the two rays start from same point, M , but end at two different points at P. then continue the two rays from P back INTO the mirror until they both meet

wish i could click the "like" button more than once..... THANK YOU!!...... btw could you clarify why the rays would diverege?....

 

[ashiqbal]

wish i could click the "like" button more than once..... THANK YOU!!...... btw could you clarify why the rays would diverege?....

actually many rays are produced from point M in all directions. we just have to show two rays that are different in angles so that we can show the extreme points when the rays reach our eyes, they are converged back at one point om our retina!

 

[bogus]

i want help in :
A glass block of length 18cm and refractive index 1.5 contains a small air bubble . viewed from one side , the bubble appears to be 8 cm from this side. how far in the block will it appear when viewed from the opposite side??
a 4cm
b 6cm
c 10cm
d 12cm

whats the given answer?

 

[multixamza01]

i got from an old work sheet . donot know the past paper number but i think its might be 4rm some book !

12 cm .
Use the formula :
Apparent Depth / Real Depth = Refractive Index

 

[SALT]

do beta particles hav mass??

 

[bogus]

do beta particles hav mass??

yes

 

[multixamza01]

do beta particles hav mass??

no . beta particles are electrons . they have negligible mass!

 

[SALT]

multixamza01 or bogus.......which one of u am i supposed 2 go with?

 

[multixamza01]

multixamza01 or bogus.......which one of u am i supposed 2 go with?

your choice

 

[Rimsa]

multixamza01 or bogus.......which one of u am i supposed 2 go with?

multixamza is right..

 

[SalmanPakRocks]

They have mass
1/1800 But that is so small so it's ignored.

 

[Spunkyfarhan]

They have mass
1/1800 But that is so small so it's ignored.

HELPPPPPPPPPPPPPPPPPP! PLZ
How to do this?

 

[Rimsa]

HELPPPPPPPPPPPPPPPPPP! PLZ
How to do this?

angle A will be 40 cuz B and C angle are 70. so apply sine rule.
7.6 (the line BC)/sin(40) = (x+3.8)/ sin(70)

x= 7.31 cm
correct me if its wrong

 

[SalmanPakRocks]

Please post maths in the maths thread! not here!

 

[Vogue]

1) what is the safety item used wid pipette?
2)how to obtain pure water from aq. NaOH. a) chromatography b) distillation c) evaporation d) titration
3) wen drawing a graph in either chem or phy ATP, is it necessary to extend the graph beyond the extreme points that r given in the table ( meaning dat if the first point i need to plot is x=30 wen y=20 then do i need to extend the line or curve till origion)???

 

[Rimsa]

1) what is the safety item used wid pipette?
2)how to obtain pure water from aq. NaOH. a) chromatography b) distillation c) evaporation d) titration
3) wen drawing a graph in either chem or phy ATP, is it necessary to extend the graph beyond the extreme points that r given in the table ( meaning dat if the first point i need to plot is x=30 wen y=20 then do i need to extend the line or curve till origion)???

1. dunt know the name. its an orange colored appratus
2. fractional distillation
3. yeah its preferable cuz sumtime you need to give the value of y when x is 0

 

[multixamza01]

They have mass
1/1800 But that is so small so it's ignored.

Yes i know , that's why i wrote negligible

 

[Vogue]

1. dunt know the name. its an orange colored appratus
2. fractional distillation
3. yeah its preferable cuz sumtime you need to give the value of y when x is 0

will u plz explain that how is it distillation?

 

[multixamza01]

will u plz explain that how is it distillation?

NaOH is soluble in water . Therefore both can be taken as miscible liquids . Fractional Distillation is the only method to separate such liquids