# Physics

posted by on .

How many electrons must be removed from an electrically neutral silver dollar to give it a charge of +2.8 µC?

• Physics - ,

Do you know the charge per electron?

number*charge per electron= total charge

solve for number.

• Physics - ,

i don't know what you mean about the charge of the electron? or what number do you times it by.

• Physics - ,

http://scienceworld.wolfram.com/physics/ElectronCharge.html

number electrons= totalcharge/chargeperelectron

• Physics - ,

q=(n*e).....(i)
where, q= charge,
n=number,
e= charge of an electron
n=q/e....(i) (from equation i)
given,q= +2.8mc= +2.8*10^-6 c
we know, charge of an electron(e)=1.6*10^-19 c

hence n= (2.8*10^-6)/(1.6*10^-19)
= 1.75*10^13
so, 1.75*10^13number of charges should ne removed.

• Physics(last line:correction) - ,

q=(n*e).....(i)
where, q= charge,
n=number,
e= charge of an electron
n=q/e....(i) (from equation i)
given,q= +2.8mc= +2.8*10^-6 c
we know, charge of an electron(e)=1.6*10^-19 c

hence n= (2.8*10^-6)/(1.6*10^-19)
= 1.75*10^13
so, 1.75*10^13number of charges should be removed.

• Physics - ,

what? i don't get it. ISn't 1.72*10^3 the number of electrons for 2.7uC?

• ÝÖíáÉ ÓÚÏÇä - ,

ÏáßäÇ ÞÖíÈ ÈÞãÇÔ ÌÇÝ ÝÍãá ÔÍäÉ ÞíãÊåÇq=3.2*10 14-

• Physics - ,

1.5x10^13