1 A 120-lb person stands on a bathroom spring scale while riding in an elevator. If the eleva- tor has (a) upward and (b) downward acceleration of g/4, what is the weight indicated on the scale in each case?

6. A skydiver of mass m = 60 kg leaps from a plane with an initial upward velocity of vo = +5 m/s. Assume the diver experiences air resistance proportional and opposite to their velocity, with drag coefficient b= 11 N/(m/s). Also assume acceleration due to gravity is g = 9.8 m/s². The velocity of the diver changes with time, as modelled by the following differential equation. m = -mg-bv dv dt Solve for u(t)= the velocity of the diver at time t, and determine the diver's terminal velocity: lim v(t) t-x

A squirrel (mass 526 g) sits at rest at the bottom of the tree. At some moment it starts running vertically up the tree and reaches a speed of 4.4 m/s in 0.96 seconds. Assuming that the acceleration is constant, a) What is the magnitude of the acceleration of the squirrel? 4.583 b) What is the magnitude of the force that the squirrel exerts on the bark of the tree during the acceleration phase? 2.410658 X

2.8 kg object. What is the value of ax the x-component of the object's acceleration?

An object with mass m, = 5.40 kg, rests on a frictionless horizontal table and is connected to a = 10.6 kg, cable that passes over a pulley and is then fastened to a hanging object with mass m, as shown in the figure. (a) Find the magnitude of the acceleration of each object. a1 Your response differs from the correct answer by more than 100%. m/s² a2 m/s2 (b) Find the tension in the cable. 35.046

10. To meet a U.S. Postal Service requirement, employees' footwear must have a coefficient of static friction of 0.5 or more on a specified tile surface. A typical athletic shoe has a coefficient of static friction of 0.800. In an emergency, what is the minimum time interval in which a person starting from rest can move 3.00 m on the tile surface if she is wearing (a) footwear meeting the Postal Service minimum and (b) a typical athletic shoe? Answers: a) 1.11 s b) 0.875 s

A mop is pushed across the floor with a force F of 44.5 N at an angle of 0 = 50.6°. The mass of the mop head is m = 2.10 kg. Calculate the magnitude of the acceleration a of the mop head if the coefficient of kinetic friction between the mop head and the floor is µ 0.355. m/s²