Aresistor with an unknown resistance is connected in parallel to a 13 ? resistor. when both resistors are connected in parallel to an emf source of 13 v, the current through the unknown resistor is measured with an ammeter to be 3
a. what is the resistance of the unknown resistor? answer in units of ? .

Ahowler monkey is the loudest land animal and, under some circumstances, can be heard up to a distance of 4.6 km. assume the acoustic output of a howler to be uniform in all directions and that the threshold of hearing is 1.0 × 10-12 w/m2. what is the acoustic power emitted by the howler

The passage that directs air to the lungs is called a. diaphragm. b. larynx. c. bronchi. d. pharynx.

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.