10 Jakob is at the start-line of a 100 meter race. His goal is to finish in 10
seconds. The race starts and Jakob crosses the finish line with a speed of
12.5 meters per second. What was his acceleration in order to finish the
race with a speed of 12.5 meters per second if he completed the race in 10
seconds? *

Acylindrical specimen of a nickel alloy having an elastic modulus of 207 gpa (30 × 106psi) and an original diameter of 10.2 mm (0.40 in.) experiences only elastic deformation when a tensile load of 8900 n (2000 lbf) is applied. compute the maximum length of the specimen before deformation if the maximum allowable elongation is 0.25 mm (0.010 in.)

Electric field of the earth. the earth has a net electric charge that causes a field at points near its surface equal to 150 n> c and directed in toward the center of the earth. (a) what magnitude and sign of charge would a 60-kg human have to acquire to overcome his or her weight by the force exerted by the earth’s electric field? (b) what would be the force of repulsion between two people each with the charge calculated in part (a) and separated by a distance of 100 m? is use of the earth’s electric field a feasible means of flight? why or why not?

What are the dimensions of the cross section that passes through the points a, f, g, and d?