When a diver gets into a tuck position by pulling in her arms and legs, she increases her angular speed. before she goes into the tuck position, her angular velocity is 5.5 rad/s, and she has a moment of inertia of 2.1 kg · m2. once she gets into the tuck position, her angular speed is 12.9 rad/s. determine her moment of inertia, in kg · m2, when she is in the tuck position. assume the net torque on her is zero.

0.89534 kgm²

Explanation:

= Final angular velocity = 12.9 rad/s

= Initial angular velocity = 5.5 rad/s

= Initial moment of inertia = 2.1 kgm²

= Final moment of inertia

As there is no external torque the angular momentum is conserved

The final moment of inertia is 0.89534 kgm²

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.

statement #3 on andre"s list is false.