The uncertainty principle states that (a) no measurement can be perfect because it is technologically impossible to make perfect measuring instruments. (b) it is impossible to measure exactly where a particle is, unless it is at rest. (c) it is impossible to simultaneously know both the position and the momentum of a particle with complete certainty. (d) a particle cannot actually have a completely certain value of momentum.

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.

According to the tide table below what time of day will the highest tide occur?

True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.