Wires diameters are usually specified by a number called the gauge. the smaller gauge wire has a larger diameter. for example, a 22 gauge wire has a diameter of 0.65 mm while a 12 gauge wire has a diameter of 2.05 mm. it is believe that the gauge number originally referred to how many times the wire is passes through a draw plate. the wire becomes thinner each time it goes through the plate. you have some long wires of different gauges and lengths. some of the wires are made of copper while others are made of aluminum. which wire has the smallest resistance?

Between a 12 gauge and a 22 gauge wire: the 12 gauge wire

Explanation:

Since the resistance in a wire is given by:

If both wires are made out of copper, the resistivity is the same.

The difference will remain in the cross area. The one with less area is the one with the greatest resistance.

Between the 2 gauge wires (22 and 12), the 12 gauge wire, with a diameter of 2.05mm is the one with smallest resistance.

where is the photo and the answer choices?

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s