If an object is moving at 7m/s and balanced forces are acting on it, what will happen to the object?

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies.

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 water vapor with the mass of 35.0 grams is cooled and condensed into water in a closed system such as a closed glass jar, what is the mass of the water after the water vapor completely condenses? a) 34.5 grams b) 35.0 grams c) 35.5 grams d) the mass cannot be determined without knowing the volume