Arock is suspended from a string; and it accelerates downward. which one of the following statements concerning the tension in the string is true?
a) the tension points downward.
b) the tension is less than the weight of the rock.
c) the tension is equal to the weight of the rock.
d) the tension is greater than the weight of the rock. the tension is independent of the magnitude of the rock's acceleration.

Aregular polygon has angkes of size 150° each.how many side has the polygon

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 ⇒

What is the weight of a feather (mass = 0.0001 kg) that floats through earth's and the moon's atmospheres?