Electric Circuits Answers

Find the extension produced in a copper wire of length 2 m and diameter 3 mm when a load of 30 N is applied. (Young’s modulus for copper = 11 x 10^11 Nm-2)

What load in kilograms must be applied to a steel wire 6 m long and diameter 1.6 mm to produce an extension of 1 mm? (Young’s modulus for steel = 20 x 10^11 Nm^-2)

A load of 20 N is applied to the ends of a wire 4 m long, and produces an extension of 0.24 mm. If the diameter of the wire is 2 mm, calculate the stress on the wire, its strain, and the value of Young’s ,modulus.

Define tensile stress, tensile strain, Young’s modulus. What are the units of dimensions of each?

A 200 kg load is hung on a wire of length 4.00 m, cross-sectional area 0.200 x 1024 m2 and Young’s modulus 8.00 x 1010N/m2. What is its increase in length?

Assume Young’s modulus of bone is 1.50 x 10^10N/m2. The bone breaks if stress greater than 1.50 x 10^8 N/m2 is imposed on it. (a) What is the maximum force that can be exerted on the femur bone in the leg if it has a minimum effective diameter of 2.50 cm? (b) If this much force is applied compressively, by how much does the 25.0 cm long bone shorten?

A steel wire of diameter 1 mm can support a tension of 0.2 kN. A steel cable to support a tension of 20 kN should have a diameter of what order of magnitude?

One description of the potential energy of a diatomic molecule is given by the Lennard-Jones potential. U= A/r^12 - B/r^6 where A and B are constants and r is the separation distance between the atoms. For the H2 molecule, take A=0.124 x 10^12eV m12 and B=1.488 x 10^-60eV m6. Find (a) the separation distance r0 at which the energy of the molecule is a minimum and (b) the energy E required to break up the H2 molecule.

What are the differences between crystalline solids, amorphous solids, and gases.

A clean glass capillary tube, of internal diameter 0.04 cm, is held vertically with its lower end below the surface of clean water in a beaker, and with 10 cm of the tube above the surface. To what height will the water rise in the tube? What will happen if the tube is now depressed until only 5 cm of its length is above the surface? The surface tension of water is 7.2 x 10-2 Nm-1.