Two students take turns lifting an object. each student lifts the object from the ground to the same height. the first student lifts the object in one third the time it takes the second student to lift the object. which of the following best compares the power of each student ? a the first student uses one third ad much power as the second student

b the first student uses the same amount of power as the second student

c the first student uses three times as much power as the seconds student

d the first student uses nine times as much power as the second student

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.

It is may 5 and you are somewhere in the northern hemisphere. if you determine that the noon sun is 51 degrees above your southern horizon, what is the latitude of your location

There are weak or strong attractive forces between atoms of liquids with a high viscosity