Author Question: Nichrome wire, often used for heating elements, has resistivity of 1.0 10-6 m at room ... (Read 33 times)

oliviahorn72 · **on:** Jul 29, 2018

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

Question 2

A 5 kg ball collides head-on with a 10 kg ball, which is initially stationary. The collision is inelastic. Which statement is true?

A) The magnitude of the change of velocity the 5 kg ball experiences is greater than that of the 10 kg ball.
B) The magnitude of the change of velocity the 5 kg ball experiences is less than that of the 10 kg ball.
C) The magnitude of the change of velocity the 5 kg ball experiences is equal to that of the 10 kg ball.
D) The magnitude of the change of the momentum of the 5 kg ball is equal to the magnitude of the change of momentum of the 10 kg ball.
E) Two of the above statements are true.