Above ground electric wires and transformers are mounted on utility poles. a support cable, called a guy wire, is sometimes attached to give the pole stability. if the guy wire makes an angle of 60 degrees with the ground, what is the measure of the angle formed by the guy wire and the pole? assume that the ground is level.

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.

How many molecules are present in 3 mols of silicon dioxide (sio2)?

Which two particles are found in the center of an atom