A 4,000-kg pick-up truck travelling at 40 m/s collides with a parked car. After the collision, if the pick-up truck continues moving at 15 m/s and the car moves at 50 m/s, determine the mass of the car.

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

Place several e-field sensors at a few points on different equipotential lines, and look at the relationship between the electric field and the equipotential lines. which statement is true? 1-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of higher voltages. 2-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of lower voltages. 3-at any point, the electric field is parallel to the equipotential line at that point.