A constant torque of 24.5 N · m is applied to a grindstone whose moment of inertia is 0.130 kg · m2. Using energy principles, and neglecting friction, find the angular speed after the grindstone has made 16.9 revolutions. Hint: the angular equivalent of Wnet = FΔx = 1 2 mvf2 − 1 2 mvi2 is Wnet = τΔθ = 1 2 Iωf2 − 1 2 Iωi2. You should convince yourself that this last relationship is correct. (Assume the grindstone starts from rest.)

One form of energy can be another type of energy. a. created to form b. transformed into c. destroyed and then created to form

Currents in dc transmission lines can be 100 a or higher. some people are concerned that the electromagnetic fields from such lines near their homes could pose health dangers. for a line that has current 150 a and a height of 8.0 m above the ground, what magnetic field does the line produce at ground level? express your answer in teslas and as a percentage of the earth’s magnetic field, which is 0.50 g. is this value cause for worry?

In which of these cases are the two wave points considered to be in phase with each other?