.

Reference: Ref 5-1

The latent heat of fusion is the amount of energy per kilogram necessary to go from point ______________ to point ______________.

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B; C

Physics & Space Science

Two wires, one copper and the other steel, of equal length stretch the same amount under an applied load P. The moduli of elasticity for each is Es 5 210 GPa and Ec 5 120 GPa. The ratio of the diameter of the copper wire to that of the steel wire is approximately:

(A) 1.00
(B) 1.08
(C) 1.19
(D) 1.32

If you push with 200 N of force against your 1500-N refrigerator and it slides across your kitchen floor at constant velocity, friction of the floor against the refrigerator must be

1) zero, 2) 200 N, 3) 1300 N, 4) 1500 N, 5) greater than 1500 N, and the force with which you push must be 6) equal and oppositely directed to the friction force. 7) the action force, and the friction the reaction force. 8) both of these. 9) none of these.

The universe is said to be closed if I. gravity is strong enough to stop the expansion in a finite time. II. the density of the universe is less than the critical density. III. the universe is finite

a. I & II b. I & III c. II & III d. I, I, & III e. none of the above

A cantilever wood pole carries force P 5 300 N applied at its free end, as well as its own weight (weight density 5 6 kN/m3). The length of the pole is L 5 0.75 m and the allowable bending stress is 14 MPa. The required diameter of the pole is approximately:

(A) 4.2 cm
(B) 5.5 cm
(C) 6.1 cm
(D) 8.5 cm