Two wires, having equal lengths and made of the same material, have resistances of 25 ohm and 49 ohm respectively. Find their relative diameters
Answers
Answer:
Two wires, having equal lengths and made of the same material, have resistances of 25 ohm and 49 ohm respectively. Find their relative diameters
Explanation:
Explanation:
Two wires, having equal lengths and made of the same material, have resistances of 25 ohm and 49 ohm respectively. What are their relative diameters?
U think you are testing people :)
Let's resistance R1 (25 ohms) and R2(49ohms). Length L metres, resistivity x ohm meter, respective cross section area A1 and A2 meter square.
25= X L/A1, ……..1
49= X L/ A2………….2
Divide 25/49 = (A2/A1)
Area = π X r^2 . Where r is radius of wires.
= π r2^2/πr1 ^2
X and L will remain same as the material and length of wire is same.
25/49= r2^2/r1^2
r2/r1= √{25/49}= 5/7.
r2=(5/7)R1.
Dia D2 is relatively 5/7 times Dia D1.
Hope I have passed on your test