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please tell me more about mod and explani more plz

HAPPY BIRTHDAY SHIPRA

WHOEVER WILL SOLVE THIS WILL BE GREAT GENIUS......

atleast try

anyone plz

please rate it

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hey..BITS Pilani is at no. 5

A 3.00 g sample containig Fe3O4 , Fe2O3 and an inert impure substance, is treated with excess KI solution in prescence of dil H2SO4. The entire iron is converted into Fe2+ along with liberation of iodine. The resulting solution is diluted to 100 mL. A 20 mL of the diluted solution requires 11.0 mL of 0.5 M Na2 S2 O3 solution to reduce the iodine present. A 50 mL of the diluted solution, after comlete extraction of the iodine requires 12.80 ml of 0.25 M KMnO4 solution in dilute H2 SO4 medium for the oxidation of Fe 2+ . Calculate the percentage of Fe2O3 and Fe3O4 in the original sample.

".....the ball reappears at the bottom of the window 2 seconds after passing the bottom on its way down ,find the height of the building ..."

See this one..

say a ball with u=20 m/s falls from x m in 1 s time...so

v=u + at

v= 30 m/s

"........the ball rebounds with the same speed with which it hits the floor ......."

So,

u=30 m/s

v=0

so t will be 3 s

SO the time is not coming equal when the ball rebounds

PLease tell where is my mistake

Is the answer 5m ??

is the window 1m high from the ground or its length is 1m

see,,if u have a good hold and able to do harder subjective questions,then u won`t be facing any problems in objective questions. But the objective questions do require more analysis and quick,wise thinking which u should develop in you,You may purchase any good objective book..

thank you..got it

ya it is across the river ,,then why 1