(a) what is torque? what happens to an object when a net torque is applied to it? (b) how is torque calculated? be sure to describe one of the two ways that we discussed in class and illustrate your answer with a diagram. (c) for an object that is in rotational equilibrium, where do you place the axis of rotation? why? (d) what is the moment of inertia of an object? how can you tell the difference between angularly accelerating an object with a large versus a small moment of inertia? [conceptual question 8 pts.][diagram 2 pts.]

The earth is constantly spinning on its axis, like you might spin a basketball on your finger. it is this spinning of the earth that causes

The frequency of vibrations of a vibrating violin string is given by f = 1 2l t ρ where l is the length of the string, t is its tension, and ρ is its linear density.† (a) find the rate of change of the frequency with respect to the following. (i) the length (when t and ρ are constant) (ii) the tension (when l and ρ are constant) (iii) the linear density (when l and t are constant) (b) the pitch of a note (how high or low the note sounds) is determined by the frequency f. (the higher the frequency, the higher the pitch.) use the signs of the derivatives in part (a) to determine what happens to the pitch of a note for the following. (i) when the effective length of a string is decreased by placing a finger on the string so a shorter portion of the string vibrates df dl 0 and l is ⇒ f is ⇒ (ii) when the tension is increased by turning a tuning peg df dt 0 and t is ⇒ f is ⇒ (iii) when the linear density is increased by switching to another string df dρ 0 and ρ is ⇒ f is ⇒

If an electric circuit is not grounded it is best to reach out and touch it to provide the ground a.true or b.false