A student built an electric circuit that consists of an ideal battery, a voltmeter with resistance RV, an ammeter with resistance RA and a resistor R. She connected all elements in the circuit as shown in Fig. (1). The voltmeter showed a reading of 1V and the ammeter showed a current of 1A. Then, another student switched between the voltmeter and ammeter Fig. (2). As a result, the voltmeter showed the reading of 2V and the ammeter showed the current of 0.5A. What is the resistance of the resistor?
Three batteries have their negative terminals connected together.
Find the voltage read by an ideal voltmeter.
A rod of length L carries a charge Q uniformly distributed along its length.
Find the electrical field at point P on the axis of the rod, a distance a away from the end of the rod.
A block of mass m and a triangular wedge of mass M move together without slipping due to a pulling force F. The triangular wedge has a slope α. There is no friction between any pair of surfaces. Derive an equation of pulling force.
A system is composed of three objects with masses m, 5m and 6m. The coefficient of kinetic friction between the objects m, 5m and the surface is 0.5. Find the acceleration of the objects.
A corner point makes angles θ1 and θ2 with the ends of a straight wire carrying current I. The distance of the point from the wire is a. What is the
magnetic field at the point?
A boy stands on a shore and pulls a rope connected to a boat. The velocity of the rope vr is constant. Prove that the closer the boat to the shore, the faster it moves.