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what is the effect on resistence of LDR when light is incident on it??
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Biology; Chemistry; Physics: Post your doubts here!
- Thread starter scouserlfc
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the resistance will decrease
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the resistance will decrease
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Please anyone know the question i posted above...
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which paper is it???
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b i) the direction of field would be from positive to negative and i think we should draw straight lines which show the directin fr +ve to -ve
bii) as we can see the terminals so we can judge that the paricle can have a positive charge because the negative plate is attracting it which cause it to move upwards.
biii) we knew that the particle wx postively charged so when it touched the plate it is going to attract the electrons as the plate has excessive electrons the nmber of electrons will increase from protons which will change the charge to negative
hope i'm correct
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You have to draw lines from the positive to negative plate. Add curved lines at the extreme ends of the plates
for part b, the explaination is that the particle was positively charged, unlike charges attract. The acceleration is because the upward force was more than the downward force, and the particle accelerated.
for the third part, the charge becomes negative. This is because there is an excess negative charge on the plate and it is transferred to the droplet too.
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it might be light purple or something like that. This is because when pottasium permangnate is reduced it changes color from purple to colorless. Actually what it does is oxidise Fe2+ to Fe3+, and as a result it is reduced itself. At end point, the solution should have been colorless as potrassium permangnate turns colorless, but there might be an excess of potassium permangnate, so the solution might be light purple, or something like that.
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Can u please draw for me..
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Thankyou but how is there an excess of potassium manganate?
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that is something that confuses me too
Still there might be some excess unreacted ions which cause the light color, but we can't be sure. Can you please clear it up Saad Mughal?P.S. he is the voice of authority here
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and we have to consider the red color of the Fe3+ ions perhaps too? I am just ending up confusing you more, so anyone an explaination please?
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that is something that confuses me too
P.S. he is the voice of authority here
When we add the potassium manganate (VII) to the solution S, the aqueous potassium manganate (VII) turns colourless when it reacts with the solution S (the colour change is brought by the reducing agent Fe). In titration, we note the end point by a colour change, when we add the final drop of potassium manganate (VII), a colour change to light-ish purple occurs because all of the solution S has been used up, this means that the final drop has not reacted and hence there is an excess of manganate (VII) ions which bring about the colour change.
Hope that helps.
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When we add the potassium manganate (VII) to the solution S, the aqueous potassium manganate (VII) turns colorless when it reacts with the solution S (the color change is brought by the reducing agent Fe). In titration, we note the end point by a color change, when we add the final drop of potassium manganate (VII), a color change to light-ish purple occurs because all of the solution S has been used up, this means that the final drop has not reacted and hence there is an excess of manganate (VII) ions which bring about the color change.
Hope that helps.
thanks. by the way just wanted to confirm are the Fe3+ ions red in water, cuz i just read online that they are yellow?
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Tag me too pls, when you get the answer
Apparatus is given so I'll just provide the procedure.
-Pour water on the cloth and wet it.
- Tie the cloth to the side of the beaker using the string.
- Place the thermometer in the beaker.
- As time passes, the reading on the thermometer decreases.
- The decrease in reading is because of evaporation which causes cooling (you guys know why).
Conclusion: When we sweat, our body is at high temperature, the sweat in normal conditions evaporates causing cooling and maintaining a constant body temperature.
Hope that helps.
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Though i am not a bio student, i am more than sure that the image formed on the retina is inverted, so i don't understand how that would be possible if the rays don't meet before the retina
Why not? When we draw ray diagrams of a converging lens, the image is formed on the point where the rays meet, and that image is inverted. No?