If the electric field exerted the same net force on a proton (m=1.67×10−27kg), how long would it take for the proton to travel 0.50 m within the field if it started from rest?

An engineer designs a roller coaster so that a car travels horizontally for 162 ft, then climbs 127 ft at an angle of 31.0° above the horizontal. it then moves 127 ft at an angle of 46.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

How do you tell if someone actually cares about you? and just say they do?

The least penetrating form of radiation is