The only force acting on a 2.0 kg body as it moves along a positive x axis has an x component fx = −6 x n, with x in meters. the velocity at x = 3.0 m is 8.0 m/s. (a) what is the velocity of the body at x = 4.0 m? (b) at what positive value of x will the body have a velocity of 5.0 m/s?

Aplane travels 1000 miles in 5 hours .what is the planes average speed?

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 ⇒

Abig box of sausages (30 kg) are lifted from the ground to the top shelf of the freezer. if the box is lifted at a constant speed, a distance of 1.75 m, what work is done by gravity?