A steel wire of length 1.90 m with circular cross-section must stretch no more than 0.280 cm when a tensile (stretching) force of 420 N is applied to each end of the wire. What minimum diameter is required for the wire?

Express your answer in millimeters. Take Young's modulus for steel to be Y = 2.00 ×10^{11} Pa .

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.

Aspecimen of oil having an initial volume of 580cm^3 is subjected to a pressure increase of 4.0 mpa, and the volume is found to decrease by 0.40 cm^3. (a) what is the bulk modulus of the material? (b) what is the compressibility of the material?

Iwill give 30 points to whoever answers ! what is the formula for actual mechanical advantage and ideal mechanical advantage?