[تبسيط]

المسألة الأولى :

Y= Y. + V.y – 0.5 g t^2

9 = 0 + V.y – 0.5 * 9.8 t^2

Vy = V.y – g t

7= V.y – 9.8 t

9 = V.y (( V.y – 7 ) / 9.8 ) - 4.9 (( V.y – 7 ) / 9.8 )^2

V.y = 15.013 m /s

Vy = V.y – g t

0 = 15.013 – 9.8 t

t = 1.532 s

Y(max) = V.y t – 0.5 g t^2

Y(max) = 15.013 * 1.532 – 0.5 * 9.8 ( 1.532 )^2

Y(max) = 11.5 m

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V.x = V.y / tan Ө

V.x = 15.013 / tan 45 = 15.013 m / s

Y = V.y t – 0.5 g t^2

0 = 15.013 t – 4.9 t^2

t = 3.1 s

X(max) = 15.013 * 3.1 = 46.54 m

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Vy = V.y – g t

Vy = 15.013 – 9.8 * 3.1 = - 15.367 m/s

V = ((Vx)^2 + (Vy)^2 )^0.5

V = (( 15.013)^2 + ( - 15.367)^2 )^0.5

V = 21.48 m/s

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