Vacum flask has inner layer of glass and outer body of plastic.the glass has a reflective metal layer..when a hot drink is poured into the flask it prevents conduction.tight lid stops the convection.when radiation tries to leave the hot drink the reflective layer of the glass reflects it back so no heat can escape.
If iodine is added to a starch solution, they react with each other and the iodine darkens to an almost pitch black.
however, if iodine is added to a solution containing no starch, it will show up only as an extremely pale brown. almost colorless and hardly visible.
when following the changes in some inorganic oxidation reduction reactions, iodine may be used as an indicator to follow the changes of iodide ion and iodine element. soluble starch solution is added. only iodine element in the presence of iodide ion will give the characteristic blue black color. neither iodine element alone nor iodide ions alone will give the color result.
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Answer:
Explanation:
The electric field outside the sphere is given as,
E = k Q /r²
here Q = n x 1.6 x 10⁻¹⁹ C
where n is the number of electons
if the dimeter of sphere d= 25 cm= 0.25 m
then the radius r = 0.125 m
we get
n= E r²/ k x 1.6 x 10⁻¹⁹ C
n = 1350N/C x (0.125m)² / (8.99 x 10⁹ N m²/C² x 1.6 x 10⁻¹⁹ C)
n = 14664731646
Answer:
position as a function of time is y = 0.05 × cos(9.9)t
Explanation:
given data
mass = 5 kg
length = 10 cm = 0.1 m
displaced = 5 cm
to find out
position as a function of time
solution
we will apply here equilibrium that is
mass × g = k × length
put here value and find k
k = 
k = 490 N/m
and ω is
ω = 
ω = 
ω = 9.9
so here position w.r.t time is
y = 0.05 × cosωt
y = 0.05 × cos(9.9)t
so position as a function of time is y = 0.05 × cos(9.9)t
Newton meter
Torque wrench
Or Just a plain Scale
