A horizontal 5-cm-diameter water jet with a velocit of 18 m/s impinges normally upon a vertical plate of J 1000 kg. The plate is held in a nearly frictionless track and is initially stationary. When the jet strikes the plate, the piaie begins to move in the direction of the jet. The water always splatters in the plane of the retreating plate. Determine (a) L acceleration of the plate when the jet first strikes it (time = 0) (b) the time it will take for the plate to reach a velocity of 9 m/s, and (c) the plate velocity 20 s after the jet first strikes the plate. Assume the velocity of the jet relative to the plate remains constant.
Chapter 2: The Chemical Basis of Life – Atoms, Molecules, and Water Overview Biology: the study of life All living organisms are a collection of atoms & molecules o Bound together and interact with each other 2.1 Atoms Overview o All living organisms are a collection of atoms & molecules o Matter: anything that contains mass and occupies space May exist in any of three states: Solid Liquid Gas o Atoms: the smallest functional units of matter that form all chemical substances and ultimately all organisms Cannot be broken down into other substances All matter is composed of atoms o Molecules: two or more atoms bonded together Atoms composed of these smaller subatomic particles Atoms Are Composed of Subatomic Particles o Many types of atoms in living organisms Hydrogen is the simplest atom o Element: a pure substance of only one kind of atom Each specific type of atom – nitrogen, hydrogen, oxygen, etc. o Subatomic particles Three types Proton (positive): a positively charged particle found in the nucleus of an atom o Atomic number: the number of protons in an atom