If a gas expands, is the work done positive, negative, or zero?

The first law of thermodynamics then reduces to

dQ = dW + dU ⇒ dU = −dW (1)

where dW is the amount of work done by the gas and dU is the change in internal energy.

Since the gas is expanding, the work being done by the gas is positive. Eqn. (1) then implies that the change in internal energy of the system must be negative, that is, the internal energy

is decreasing. The only true statements are then:

• The work done by the gas is positive, and no heat exchange occurs.

• The internal energy of the system decreases.

freeborn women in ancient rome were citizens (cives), but could not vote or hold political office. because of their limited public role, women are named less frequently than men by roman historians. but while roman women held no direct political power, those from wealthy or powerful families could and did exert influence through private negotiations. exceptional women who left an undeniable mark on history range from lucretia and claudia quinta, whose stories took on mythic significance; fierce republican-era women such as cornelia, mother of the gracchi, and fulvia, who commanded an army and issued coins bearing her image; women of the julio-claudian dynasty, most prominently livia (58 bc-ad 29), who contributed to the formation of imperial mores; and the empress helena (c.250–330 ad), a driving force in promoting christianity.

women in the ancient greek world had few rights in comparison to male citizens. unable to vote, own land, or inherit, a woman’s place was in the home and her purpose in life was the rearing of children. this, though, is a general description, and when considering the role of women in ancient greece one should remember that information regarding specific city-states is often lacking, is almost always from male authors, and only in athens can their status and role be described in any great detail. neither are we sure of the practical and everyday application of the rules and laws that have survived from antiquity. we do know that spartan women were treated somewhat differently than in other states. for example, they had to do physical training like men, were permitted to own land, and could drink wine.

answer; deviation iq; //(a)