Masses of three wire of copper are in ratio 1:3:5, and their length ar...
Ratio of masses of wires
(
m1, m2, m3) = 1 : 3 : 5
Ratio of length of wires
Electrical resistance is given by
The correct answer is: 125 : 15 : 1
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Masses of three wire of copper are in ratio 1:3:5, and their length ar...
Ratio of masses of wires
(
m1, m2, m3) = 1 : 3 : 5
Ratio of length of wires
Electrical resistance is given by
The correct answer is: 125 : 15 : 1
Masses of three wire of copper are in ratio 1:3:5, and their length ar...
< b="" />Given Information:< />
- The masses of three wires of copper are in the ratio 1:3:5.
- The lengths of the wires are in the ratio 5:3:1.
< b="" />To Find:< />
The ratio of their electrical resistance.
< b="" />Solution:< />
To find the ratio of their electrical resistance, we need to understand the relationship between resistance, length, and mass in a wire.
< b="" />1. Resistance and Length:< />
The resistance of a wire is directly proportional to its length. This means that as the length of a wire increases, its resistance also increases.
< b="" />2. Resistance and Mass:< />
The resistance of a wire is inversely proportional to its mass. This means that as the mass of a wire increases, its resistance decreases.
< b="" />Ratio of Masses:< />
The masses of the three wires are in the ratio 1:3:5.
< b="" />Ratio of Lengths:< />
The lengths of the wires are in the ratio 5:3:1.
< b="" />Calculating the Ratios:< />
Let's assume the masses of the wires are m1, m2, and m3, and the lengths of the wires are l1, l2, and l3.
Given:
m1 : m2 : m3 = 1 : 3 : 5
l1 : l2 : l3 = 5 : 3 : 1
< b="" />Masses:< />
Let's assume the mass of the first wire is m1. Then, the masses of the second and third wires can be calculated as follows:
m2 = 3m1
m3 = 5m1
< b="" />Lengths:< />
Let's assume the length of the first wire is l1. Then, the lengths of the second and third wires can be calculated as follows:
l2 = (3/5)l1
l3 = (1/5)l1
< b="" />Resistance and Mass Relationship:< />
The resistance of a wire is inversely proportional to its mass. Therefore, the ratio of their resistances will be the inverse of the ratio of their masses:
Resistance1 : Resistance2 : Resistance3 = 1/m1 : 1/m2 : 1/m3
< b="" />Resistance and Length Relationship:< />
The resistance of a wire is directly proportional to its length. Therefore, the ratio of their resistances will be the same as the ratio of their lengths:
Resistance1 : Resistance2 : Resistance3 = l1 : l2 : l3
< b="" />Calculating the Ratios:< />
Now, let's substitute the values of masses and lengths into the equations:
Resistance1 : Resistance2 : Resistance3 = (1/m1) : (1/m2) : (1/m3)
= (1/m1) : (1/(3m1)) : (1/(5m1))
= 1 : 1/3 : 1/5
Resistance1 : Resistance2 : Resistance3 = l1 : l2 : l3
= l1 : (3/5)l1 : (1/5)l1
= 1 : 3/5 : 1/5
< b="" />