Using the principles to be developed in chapter 3 on equilibrium, one can determine that the tension in cable ab is 143.4 n. determine the moment about the x-axis of this tension force acting on point a. compare your result with the moment of the weight w of the 15-kg uniform plate about the x-axis. what is the moment of the tension force acting at a about line ob?

10 is the . . .

//(b) both involve the use of levers;

The figure is missing but we can answer anyway.the correct answer is "releasing the string". in fact, when the person is holding the bow and the arrow, the kinetic energy of the arrow is still zero (because the arrow is not moving). the moment the arrow is released, it acquires a velocity v, so its kinetic energy will become different from zero: where m is the mass of the arrow and v its velocity.  all the other options, instead, do not increase the kinetic energy of the system: -  pulling farther back on the string : this will just increase the elastic potential energy of the system-  holding the arrow higher: this will increase the gravitational potential energy of the system (which is given by u=mgh, where h is the height above the ground)-  decreasing the mass of the arrow: this will decrease the gravitational potential energy of the system (which is given by u=mgh, where m is the mass)