Asoccer ball is kicked horizontally off a 22 meter high hill and lands 35 meters from the edge of the hill. determine the initial horizontal velocity of the soccer ball

y = y0 +v0*t +0.5at^2  

where y0 = initial vertical position = 22m  

y = final vertical position = 0m  

v0 = initial vertical velocity = 0 m/s  

a = acceleration = -9.8 m/s^2  

t = time in seconds  

0 = 22 +0*t + 0.5(-9.8)t^2  

t^2 = 22/4.9 = 4.49 s^2  

t = 2.12 s  

So it traveled 35m in 2.12 s  

the horizontal distance traveled is determined by:  

x = x0 +v0*t +0.5at^2  

but here a in the horizontal direction is 0 m/s^2  

and v0 is in the velocity in the horizontal direction in this equation  

35 m = 0 +v0*t  

35 m = v0(2.12 s)  

v0 = 16.5 m/s  

So the ball was kicked 16.5 m/s in the horizontal direction

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia