Physics: Electrostatics MCQs

Two protons A and B are placed between the two plates of a parallel plate capacitor charged to potential difference V as shown in fig. Then the force on proton A is –

[RPET – 1993]

The magnitude of magnetic flux density (B) in micro Teslas (T), at the center of a loop of wire wound as a regular hexagon of side length 1 m carrying a current (I = 1A) and placed in vacuum as shown in the figure is _______ .

The capacity of a condenser is 10µF. It has been charged to a potential difference of 100V. It is now connected in parallel to another uncharged condenser the common potential is 40V. The capacitance of the other condenser is –

[RPET – 1993]

Consider an electron, a neutron and a proton initially at rest and placed along a straight line such that the neutron is exactly at the center of the line joining the electron and proton. At t = 0, the particles are released but are constrained to move along the same straight line. Which of these will collide first?