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LUCKY_DIMON [66]
3 years ago
8

1. An airow is shot horizontally from a crossbow 1.5 m above the ground. The initial velocity is 45

Physics
1 answer:
Amanda [17]3 years ago
4 0

Answer:

Time taken by the arrow to travel along to hit the ground is 0.55 seconds.

Explanation:

The only "force" acting on the "crossbow" to cause it to "hit" the ground is "gravity". There is no initial velocity downward when it shoot.

d=v_{i} t+\frac{1}{2} t^{2}

d = the displacement of the object  

t = the time for which the object moved  

a = acceleration of the object  

v_i = the initial velocity of the object

Given values

d = 1.5 m

t = unknown

a=g=9.8 \mathrm{m} / \mathrm{s}^{2}

\mathrm{V}_{\mathrm{i}}=0 \mathrm{m} / \mathrm{s}

1.5 \mathrm{m}=0(\mathrm{t})+\frac{1}{2}\left(9.8 \mathrm{m} / \mathrm{s}^{2}\right) \mathrm{t}^{2}

1.5=0+4.9 \mathrm{t}^{2}

\mathrm{t}^{2}=\frac{1.5}{4.9}

t^{2}=0.306 \mathrm{s}

Square root both sides

t=\sqrt{0.306}

t = 0.55 s

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