(II) The terminal velocity of a 3 x 10⁻⁵ kg raindrop is about 9 m/s. Assuming a drag force F_D = -bv , determine (b) the time required for such a drop, starting from rest, to reach 63% of terminal velocity.

Suppose a 65-kg person jumps from a height of 3.0 m down to the ground.

(c) Estimate the decelerating force if the person lands stiff-legged so d ≈ 1.0 cm .

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(II) The drag force on large objects such as cars, planes, and sky divers moving through air is more nearly F_D = -cv² .

(a) For this quadratic dependence on v, determine a formula for the terminal velocity vτ , of a vertically falling object..

(III) Air resistance acting on a falling body can be taken into account by the approximate relation for the acceleration: a = dv/dt = g ― kv , where k is a constant. (

b) Determine an expression for the terminal velocity, which is the maximum value the velocity reaches.

(II) A 2.0-kg purse is dropped from the top of the Leaning Tower of Pisa and falls 55 m before reaching the ground with a speed of 27m/s . What was the average force of air resistance?

An 800-kg car is traveling along a horizontal road directly towards a cliff. The driver notices and brakes, resulting in a 5,000-N net force slowing the car down. If the car's initial speed was 20 m/s and the car stops just before going over the cliff, how far away was the car from the cliff when the driver hit the brakes?

(II) A child on a sled reaches the bottom of a hill with a velocity of 10.0 m/s and travels 25.0 m along a horizontal straightaway to a stop. If the child and sled together have a mass of 60.0 kg, what is the average retarding force on the sled on the horizontal straightaway?