Jacob and Sophia are playing with a merry-go-round on a playground. The merry-go-round can be modeled as a flat disk with massM= 223.0kg and radiusR= 3.3 m that freely rotates horizontally without frictionabout its center axis. When the merry-go-round is already spinning at23 rotations per minute, Jacob exerts a constant forceFJ= 12.3 Ntangent to the outer edge of the merry go round in the direction of themerry-go-round’s rotation. At the same time Sophia puts her foot ata distancer= 3.1 m from the center, which exerts a constant force offrictionFS= 21.2 N. How long will it take for the merry-go-round tocome to a stop?

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.

You've already seen the value of 9.8 in this lesson. what's this value called? what quantity does it represent?

What electron configurations do atoms usually achieve by sharing electrons to form covalent bonds?