A point charge of 7nC is at a fixed location of (4mm, 3mm, 0). Another point charge of -5nC is located at a fixed position of (3mm, 4mm, 0). What will be the force acting on an electron placed in the origin of the coordinate system

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If an astronaut takes an object to the moon the following is true (choose only one). a the mass will change but the weight will be the same. b both the mass and the weight of the object will be the same. c the weight will change but the mass will be the same. d both the mass and the weight of the object will change.

You are given a vector a = 125i and an unknown vector b that is perpendicular to a. the cross-product of these two vectors is a × b = 98k. what is the y-component of vector b?