He force with which the wind pushes the stone is a drag force. Assuming a stone of mass 25 kg has a vertical cross-sectional area of 0.05 m2, a drag coefficient C=0.7C=0.7, and the air density is 1.21 kg/m3, what is the wind speed along the ground needed to maintain the stone's motion once it has started moving? INCLUDE UNITS in your answer!

If football was tossed in air without gravity or friction the ball would go into space

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)

It has more electrons than an neutral object