Information about commonly used gadgets or devices are based on properties of newton's three laws

Remote control helicopter is best example for the Newton's third law of motion.

Newton's third law of motion is every action has equal and opposite reaction.

Wings of helicopter exert force on wind.

then after the helicopter flies.

Answer : - when there are capacitors and inductors in an ac circuit the phase between the voltage and current is

At the maximum height of the ball, the velocity will be zero. will also take half the total time, 3.125 s. 
now use the  
δd = vf*t - 1/2at^2 

by setting the final time at the moment of the apex of the height, vf becomes 0. 
so the equation will  
δd = - 1/2at^2 

the equation now resembles the change in height from the ground to the maximum height 

δd = - 1/2at^2 = - 1/2 (-9.8 m/s^2) (3.125 s)^2 = 47.8 m