Three objects with masses m₁ = 3.8 kg, m₂ = 12 kg, and m 19 kg, respectively, are attached by strings over frictionless pulleys as indicated in the figure below. The horizontal surface exerts a force of friction of 30 N on m2. If the system is released from rest, use energy concepts to find the speed of m¸ after it moves down 4.0 m. m/s m m2 mg

In order for Jane to return to base camp, she needs to swing across a river of width D that is filled with alligators. She must swing into a wind exerting constant horizontal force F, F = 110 N, L = 40.0 m, 0 = 50.0°, and her mass to be 50.0 kg. Wind →F Tarzan! Jane (a) with what minimum speed (in m/s) must Jane begin her swing to just make it to the other side? (If Jane can make it across with zero initial velocity, enter 0.) m/s on a vine having length L and initially making an angle with the vertical (see below figure). Take D = 48.0 m, (b) Shortly after Jane's arrival, Tarzan and Jane decide to swing back across the river (simultaneously). With what minimum speed (in m/s) must they begin their swing? Assume that Tarzan has a mass of 80.0 kg. m/s

R=2.00 12V 2.00 4.00 4.002 What is the current in one of the 4.0 Q resistors? An isolated point charge q is located at point X. Two other points Y and Z are such that YZ2 XY. Y X What is (electric field at Y)/(electric field at Z)?