A 70kg girl jumps out of a moving boat of mass 30 kg onto the bank with a velocity of 5 m/s. Which velocity does the body begins to move backwards?

The dissociation energy of a molecule is the energy required tobreak apart the molecule into its separate atoms. the dissociationenergy for a particular molecule is 5.48 x 10-18 j.suppose that this energy is provided by a single photon. determinethe (a) wavelength and (b) frequency of the photon

Scientists use laser range-finding to measure the distance to the moon with great accuracy. a brief laser pulse is fired at the moon, then the time interval is measured until the "echo" is seen by a telescope. a laser beam spreads out as it travels because it diffracts through a circular exit as it leaves the laser. in order for the reflected light to be bright enough to detect, the laser spot on the moon must be no more than 1.0 km in diameter. staying within this diameter is accomplished by using a special large-diameter laser. part a if λ = 540nm , what is the minimum diameter of the circular opening from which the laser beam emerges? the earth-moon distance is 384,000 km. express your answer to two significant figures and include the appropriate units.

Iron is a transition metal with multiple oxidation numbers. (answer the following) a. what is the iron (ii) ion? how does it differ from the iron (iii) ion? b. if iron were to bond with oxygen, predict the formula for each oxidation number of iron. c. how would each formula be named?