A polythene piece is rubbed with wool and it has been found to acquire a negative charge of 3*10^-7C. 1. how many electrons have transferred from wool to polythene piece. 2. how much is the transfer of mass from wool to polythene takes place.
Answers
(a) When polythene is rubbed against wool, a number of electrons get transferred from wool to polythene. Hence, wool becomes positively charged and polythene becomes negatively charged.
Amount of charge on the polythene piece, q = −3 × 10−7 C
Amount of charge on an electron, e = −1.6 × 10−19 C
Number of electrons transferred from wool to polythene = n
n can be calculated using the relation, q = ne
n equals q over e
=fraction numerator minus 3 x 10 to the power of minus 7 end exponent over denominator minus 1.6 x 10 to the power of minus 19 end exponent end fraction
= 1.87 × 1012
Therefore, the number of electrons transferred from wool to polythene is 1.87 × 1012.
(b) Yes. There is a transfer of mass occur. This is because an electron has mass,
as we know
me = 9.1 × 10−3 kg
Total mass transferred from wool to polythene,
m = me × n
= 9.1 × 10−31 × 1.85 × 1012
= 1.706 × 10−18 kg
Hence, a negligible amount of mass is transferred from wool to polythene.
Answer:
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electrons have transferredfrom wool to polythene piece.transfer of mass from wool to polythene takes place.