In Boston the magnetic field is 17 degrees from the vertical and has a magnitude of 5.8⋅10−5T. A 2 m horiztonal wire carries a 20 A current to the north. Note that the angle of the velocity from the field is 90−17 degrees. What is the magnitude of the force on the wire?

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct

Many science fiction movies and tv shows have detected using a nuclear weapon to destroy astroids what problems does plait see with this plan

Multiple choice. choose the one alternative that best completes the statement or answers the question. 1) if the force on an object is in the negative direction, the work it does on the object must be 1) a) negative. b) positive. c) the work could be either positive or negative, depending on the direction the object moves. 2) a truck has four times the mass of a car and is moving with twice the speed of the car. if kt and kc refer to the kinetic energies of truck and car respectively, it is correct to say that 2) a) kt = 16kc . b) kt = 1 2 kc. c) kt = kc . d) kt = 2kc . e) kt = 4kc . 3) you and your friend, who weighs the same as you, want to go to the top of the eiffel tower. your friend takes the elevator straight up. you decide to walk up the spiral stairway, taking longer to do so. compare the gravitational