Q10.17: which of the following statements concerning simple harmonic motion is false? a : a restoring force acts on an object in simple harmonic motion that is directed in the same direction as the object's displacement. b : a restoring force acts on the object that is proportional to the object's displacement from its equilibrium position. c : during simple harmonic motion, the net force on the object is zero when it is at its equilibrium position. d : the displacement versus time graph for an object in simple harmonic motion resembles the sine or cosine function. e : the amplitude of the motion of an object in simple harmonic motion is the maximum distance the object moves from its equilibrium position.

In raising a 6200-n piano with a pulley system, the movers note that, for every 2.2 m of rope pulled down, the piano rises 0.12 m . ideally, find the force required to lift the piano.

Identify the arrows that show the correct direction of heat transfer. 66°f 112°f 98°f

In a thunderstorm, charge builds up on the water droplets or ice crystals in a cloud. thus, the charge can be considered to be distributed uniformly throughout the cloud. for the purposes of this problem, take the cloud to be a sphere of diameter 1.00 kilometer. the point of this problem is to estimate the maximum amount of charge that this cloud can contain, assuming that the charge builds up until the electric field at the surface of the cloud reaches the value at which the surrounding air breaks down. this breakdown means that the air becomes highly ionized, enabling it to conduct the charge from the cloud to the ground or another nearby cloud. the ionized air will then emit light due to the recombination of the electrons and atoms to form excited molecules that radiate light. in addition, the large current will heat up the air, resulting in its rapid expansion. these two phenomena account for the appearance of lightning and the sound of thunder. take the breakdown electric field of air to be eb=3.00ă—106n/c. part a estimate the total charge q on the cloud when the breakdown of the surrounding air is reached. express your answer numerically, to three significant figures, using ďµ0=8.85ă—10â’12c2/(nâ‹…m2) .