Akash, a punter in a football game kicks a ball from the goal line at 52.0° from the horizontal at 29.0 m/s. a) what is the hang time of the punt ? b) how far down field does the ball land?

(a)

θ = angle from the goal line = 52.0 deg

v₀ = initial velocity of launch = 29 m/s

consider the motion of the ball along the vertical direction

Y = vertical displacement = 0 m

a = acceleration = - 9.8 m/s²

v' = initial velocity along the Y-direction = v₀ Sinθ = (29) Sin52 = 22.85 m/s

t = hang time

using the equation

Y = v' t + (0.5) a t²

0 = (22.85) t + (0.5) (- 9.8) t²

t = 4.7 sec

b)

Consider the motion along horizontal direction

X = displacement along X-direction

t = time taken = 4.7 sec

v'' = initial velocity along the X-direction = v₀ Cosθ = (29) Cos52 = 17.85 m/s

displacement along the X-direction is given as

X = v'' t

X = (17.85) (4.7)

X = 83.89 m

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

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