The collar of mass m slides on the rough horizontal shaft under the action of the force f of constant magnitude f ≤ mg but variable direction. if ! = kt where k is a constant, and if the collar has a speed v1 to the right when ! = 0, determine the velocity v2 of the collar when ! reaches 90°. also determine the value of f which renders v2 = v1.

The horse latitudes-high-pressure zones about 30 degrees north and 30 degrees south of the equator.-warm air traveling away from the equator cools and sinks-weather tends to be clear and drythe doldrums-low-pressure near equator-air rises and spreads out toward the poles-rising moist air produces clouds and heavy rainthe westerlies-blow from the west-move from the horse latitudes toward the poles.-bring storms across much of the united statesthe tradewinds-blow from the east-move from the horse latitudes toward the equator  -strong, steady winds