The mean free path of an oxygen molecule is 2.0 � 10-5 m, when the gas is at a pressure of 120 pa and a temperature of 275 k. the atomic mass of oxygen is 16.0 g/mol, the boltzmann constant is 1.38 � 10-23 j/k, avogadro's number is 6.02 � 1023 molecules/mole, and the ideal gas constant is j/mol � k = 0.0821 l � atm/mol � k. the radius of an oxygen molecule is closest to
0.28 nm.
0.24 nm.
0.22 nm.
0.26 nm.
0.30 nm.

The plum pudding model of the atom state that ?

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 ⇒

Brutus, the dog, is pulling a bone to the left with a force of 20 n. lassie, another dog, is pulling a bone to the right with a force of 18n. what is the net force? a. b. c.