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(a).       Three forces, F1 = 150 N, F2 = 10.0 N and F3 = 30.0 N act on a 15 kg object. If F1 and F2 act in same direction, while F3 acts in the opposite direction, what is the              magnitude of the acceleration of the object?                                                                                          (2.5 points)      b).      To negotiate a curve of radius 38 m, the maximum force of static friction (centripetal force) that can act on a 1,350-kg car going around the curve is 8,200 N.            What speed limit should be posted for the curve so that cars can negotiate safely?                                                                                                       (3.0 points)                                                                                                                        c).         With what speed must a 75 kg object be going to have a linear momentum of 925 kg m/s?             (1.5 points)

(a).       At what depth in the ocean is the gauge pressure acting on a hatch that has an area of 5.5 m2 equal to 490,000 Pa?   (Take g = 9.80 m/s2 and density of sea water            to be 1020 kg/m3)                                                                                                                    (1.5 points)       (b).         What is the force on the hatch area due to only the gauge pressure?                                                  (1.5 points) (c).         A hydraulic lift in a garage has two pistons: a small one with a cross-sectional area of 4.00 cm2 and large one with a cross-sectional area 250 cm2. If this lift is              designed to raise a 3500 kg car, what minimum force must be applied to the small piston and what is the pressure of the hydraulic lift?                     (3.0 points)

(a).        A 92 kg high jumper running 11 m/s executes a jump. (i).       What is his kinetic energy before the jump?                                                                                      (1.5 points)  (ii).     Using the law of conservation of energy or otherwise, calculate how high he can jump.                    (1.5 points) (b).        A 15 kg mass hangs on a spring causing it to stretch by 0.22 m. (i).         Calculate the spring constant.                                                                                                             (1.5 points) (ii).       Calculate the work done in stretching the spring by 0.22 m.                                                              (1.5 points)

Which of the following molecules is most easily able to diffuse across the cell membrane?

A competitive inhibitor interferes with the _________ site of the enzyme so a substrate cannot bind.

Which of the following is found in all prokaryotic cells, but not found in all eukaryotic cells?

Which of the following statements about transport through the plasma membrane of a cell is correct?

DNA, thylakoids, and stroma are components of which eukaryotic organelle?

How is the majority of ATP produced in cells?

For each statement below, determine whether each condition will promote microtubule polymerization or depolymerization. The addition of a drug that prevents GDP-tubulin from dissociating from the polymer will promote microtubule [1]. The addition of a drug that inhibits GTP hydrolysis in subunits incorporated into the polymer will promote microtubule [2]. The addition of a drug that caps the minus end of the microtubule and prevents subunit exchange at the minus end will promote microtubule [3]. The addition of a drug that promotes GTP hydrolysis in the microtubule will promote microtubule [4].