Question

a stone will fall straight to ground in 4 s whendropped from rest from the top of a 60 m high building. if the stone is thrown horizontally from this building with a velocity of 8 m/s , at what distance x beyong the building will it strike the ground?

Answer 1

32 m

Step-by-step explanation:

When the stone is thrown horizontally, its initial horizontal velocity (Vx) is 8 m/s, and its initial vertical velocity (Vy) is 0. The stone will follow a parabolic path, with the same vertical motion as the stone dropped from rest.

Vertical motion:

Initial height (h) = 60 m

Vertical acceleration (a) = -9.8 m/s^2 (downward direction)

Time of flight (t) = 4 s

Final vertical velocity (Vy) = Vy + a*t = 0 + (-9.8 m/s^2)*4 s = -39.2 m/s

Vertical displacement (y) = Vyt + 0.5at^2 = 0 + 0.5(-9.8 m/s^2)*(4 s)^2 = -78.4 m (negative because the stone falls below the initial height)

Horizontal motion:

Initial horizontal velocity (Vx) = 8 m/s

Horizontal acceleration (ax) = 0 (no acceleration in horizontal direction)

Time of flight (t) = 4 s

Horizontal displacement (x) = Vx*t = 8 m/s * 4 s = 32 m

Therefore, the stone will strike the ground at a horizontal distance of 32 meters beyond the building.