Question

a coil of wire of cross section 0.75 mm^2 weighs 125g in air and 115g in water. the length of the coil in cm is​
(with explanation )

Answer 1

Answer:

Explanation:

Solution :-

Loss of weight of coil in water

= (125 - 115)g

= 10 g

Area of cross-section

A = 10⁻² m²

= 0.75 mm²

= 0.75 × 10⁻⁶ m²

Therefore, Weight of water displaced = 10⁻² kg

Volume of coli = Length of coil (L) × Area of cross-section (A)

L = Volume of coil/A

L = 10⁻⁵/0.75 × 10⁻⁶

Hence, the length of the coil is 10⁻⁵/0.75 × 10⁻⁶.

Answer 2

Answer:

Explanation:

M = Mass in air

m = Mass in water

Loss of weight in water = Buoyant Force

(M-m)g = density of water x g x Volume of the wire

125-115 = 1g/cc x Volume of the wire

Volume of wire = 10 cc

Volume = Cross Section area x Length

10 cm^3 = 0.75 mm^2 x Length

10 cm^3 = 0.0075 cm^3 x Length

Length of the wire = $\frac{10^{5} }{75} cm$

Therefore , it is your answer .

I hope it helps you . If you have any doubts , then don't hesitate to ask.