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Studentka2010 [4]
3 years ago
5

A man is standing on the edge of a 20.0 m high cliff. He throws a rock horizontally with an initial velocity of 10.0 m/s.

Physics
1 answer:
kherson [118]3 years ago
5 0

Answer:

<em>a. The rock takes 2.02 seconds to hit the ground</em>

<em>b. The rock lands at 20,2 m from the base of the cliff</em>

Explanation:

Horizontal motion occurs when an object is thrown horizontally with an initial speed v from a height h above the ground. When it happens, the object moves through a curved path determined by gravity until it hits the ground.

The time taken by the object to hit the ground is calculated by:

\displaystyle t=\sqrt{\frac{2h}{g}}

The range is defined as the maximum horizontal distance traveled by the object and it can be calculated as follows:

\displaystyle d=v.t

The man is standing on the edge of the h=20 m cliff and throws a rock with a horizontal speed of v=10 m/s.

a,

The time taken by the rock to reach the ground is:

\displaystyle t=\sqrt{\frac{2*20}{9.8}}

\displaystyle t=\sqrt{4.0816}

t = 2.02 s

The rock takes 2.02 seconds to hit the ground

b.

The range is calculated now:

\displaystyle d=10\cdot 2.02

d = 20.2 m

The rock lands at 20,2 m from the base of the cliff

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