Nichrome wire, often used for heating elements, has resistivity of 1.0 × 10-6 ? ? m at room temperature. What length of No. 30 wire (of diameter 0.250 mm) is needed to wind a resistor that has 50 ohms at room temperature?

A) 3.66 m
B) 2.45 m
C) 0.61 m
D) 6.54 m
E) 22.4 m

Answer: B

Physics & Space Science

You might also like to view...

Sound waves in the interstellar medium

A) cannot exist at all. B) travel so slowly that they are undetectable. C) cannot be heard by human ears, but do indeed travel through the gas. D) travel extremely quickly and are therefore very loud.

View
Physics & Space Science

What is the magnetic moment of a rectangular loop of 120 turns that carries 6.0 A if its dimensions are 4.0 cm × 8.0 cm?

A) 0.023 A?m2 B) 0.23 A?m2 C) 2.3 A?m2 D) 23 A?m2 E) 230 A?m2

View
Physics & Space Science

The Rydberg equation is used to

a.determine the ratio of the electron charge to its mass b. calculate the wavelengths of different spectral lines of hydrogen c. measure the mass of the hydrogen atom d. calculate the wavelengths of different transitions in energy level of electrons in helium

View
Physics & Space Science

Ralph walks 3 m to the left in 2 seconds, then 4 m to the right in 3 seconds. Next, he stops for 3 seconds, and finally walks 5 m to the left in 4 seconds

Ralph's displacement is closest to:

1.0 m 2.2 m 3.4 m 4.6 m 5.8 m 6.10 m 7.12 m 8.14 m 9.The negative of one of the choices above 10.Impossible to determine

View
Physics & Space Science