Question

13. Two identical spheres of mass 1.0 kg each carry a charge of 1.0 C. In comparing the electric and gravitational forces between the spheres, it can be concluded that a. Fe is greater than Fo b. Fa is greater than Fe c. the two forces are equal d. the forces cannot be compared without knowing if the signs of the charges are the same or opposite e. the forces cannot be compared without knowing the distance between the spheres There is a potential difference between a pair of parallel plates, and plate A is positive and plate B is negative. A positive test charge is placed between the two plates. The 14. plate with the higher electric potential is: a. plate A b. plate B c. plates A and B have the same potential d. the plate that is closer to the positive charge e. it depends on the mass of the test charge Which of the following statements about field lines is true? a. Field 15. lines are always perpendicular to the surface of the object creating the field b. Field lines always point in the direction of the motion of the object creating the field. c. Field lines never cross d. Field lines are always straight. e. Field lines represent a force that remains uniform along the entire length of the field line. 16. A series of wave fronts in a wave tank travel toward an opening in a barrier. To increase the amount of visible diffraction, one could a. increase the wave's amplitude b. decrease the wave's frequency c. increase the width of the opening in the barrier d. decrease the distance between the source of the waves and the barrier e. use a shorter wavelength When two wave sources are in-phase, and the wave from one source has to travel one- half wavelength further from the wave from the other source, there will be a. destructive interference b. constructive interference c. alternating constructive and destructive interference d. simultaneous constructive nor destructive interference e. no interaction 17.

Answer 1