A piano wire has a radius of 0.50 mm. One end is fixed and the ...

[fox]

A piano wire has a radius of 0.50 mm. One end is fixed and the other is wrapped around a tuning peg, which has a diameter of 3.5 mm and is 80 cm away. After the wire just becomes taut, the peg is given three full turns.
 
  What is the tension in the wire? Young's modulus for steel is 20  1010 N/m2. A) 3.8 kN
  B) 4.3 kN
  C) 6.5 kN
  D) 8.7 kN
  E) 9.8 kN

Question 2

The inductance of a solenoid 16.0 cm long with a cross-sectional area of 1.00  10-4 m2 is 1.00 mH. How many turns of wire does this solenoid have?
 
  A) 318,000
  B) 159,000
  C) 1130
  D) 282
  E) 150

[Tonny]

Answer to Question 1

C

Answer to Question 2

C

[fox]

Thanks for the timely response, appreciate it

[ryhom]

Gracias!