# Physics

posted by .

A rectangular piece of gold is 3.1 cm long and 3 cm wide. Resistivity of gold is 2.4*10^-8. How deep is the piece when it displays a resistance of R = 1.65 μω for a current that flows along the depth-direction?

I used R=(p*l)/A and solved for l. I got the answer wrong. For the area I used 0.03*0.03 as the cross sectional area. What did I do wrong?

• Physics -

The area is 0.03 * d, and you are supposed to solve for d, knowing the total resistance. Current flow is along the length, which you know to be 3.1 cm.

There is possibly another problem as well. The resistivity of gold is approximately 2.44 × 10-8 ohm-m. The way you are using it, with gold block dimensions in cm, you have to change the value of p to 2.44 × 10-6 ohm-cm

• Physics -

Thank you.

## Similar Questions

1. ### Physics

Can the following equation be used to solve the question?
2. ### Physics

A rectangular piece of gold is 3.8 cm long and 2.5 cm wide. How deep is the piece when it displays a resistance of R = 1.35 μω for a current that flows along the depth-direction?
3. ### PHYSICS

A rectangular piece of gold is 3.6 cm long and 3.5 cm wide. How deep is the piece when it displays a resistance of R = 1.51 ìù for a current that flows along the depth-direction?
4. ### physics

A rectangular piece of gold is 2.5 cm long and 2.6 cm wide. How deep is the piece when it displays a resistance of R = 1.39 μω for a current that flows along the depth-direction?
5. ### physics

a piece of gold aluminuim alloy weighs 100g in air and 80g in water.what is the weight of the gold in the alloy if the relative density of gold is 19.3 and that of aluminium is 2.5
6. ### physic

The resistivity of gold is at a temperature of 20°C. A gold wire, 1.8 mm in diameter and 14 cm long, carries a current of 480 ma. The power dissipated in the wire is closest to:
7. ### Algebra

The purity of gold is measured in karats. Twenty-four karat gold is pure gold and k karat gold is k/24 gold by mass. One piece of 16-karat gold jewelry has a mass of 30 grams and another piece of 10-karat gold jewelry has a mass of …
8. ### Algebra 2

The purity of gold is measured in karats. Twenty-four karat gold is pure gold and k karat gold is k/24 gold by mass. One piece of 16-karat gld jewelry has a mass of 30 grams and another piece of 10-karat gold jewelry has a mass of …
9. ### physics

A rectangular piece of gold is 2.6 cm long and 3.9 cm wide.The piece displays a resistance of 1.47 ìÙ when a current flows along the depth-direction. In cm, how deep is the piece?
10. ### science

density of gold is 19.32 g/cm^3.A piece of gold leaf is 2.50 cm on each side and 0.100 mm thick,How many atoms of gold are in this piece of gold leaf?

More Similar Questions