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3 years ago

A 40kg rock falls off a cliff that is 50 meters high. How fast is the speed of the rock when it hits the ground

Physics

1 answer:

Oksi-84 [34.3K]3 years ago

7 0

31.3m/s

Explanation:

Given parameters:

Mass of rock = 40kg

Height of cliff = 50m

Unknown:

Speed of rock when it hits ground = ?

Solution:

We are going to use the appropriate motion equation to solve this problem

The rock is falling with the aid of gravitational force. The force is causing it to accelerate with an amount of velocity.

Using;

V² = U² + 2gH

V = unknown velocity

U = initial velocity = O

g = acceleration due to gravity = 9.8m/s²

H = height of fall

since the initial velocity of the bodyg is 0

V² = 2gH

V= √2gH = √2 x 9.8 x 50 = 31.3m/s

learn more:

Velocity brainly.com/question/4460262

#learnwithBrainly

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alexandr402 [8]

Answer:

Object should be placed at a distance, u = 7.8 cm

Given:

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Solution:

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where

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Now,

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3 years ago

A large crane consists of a 20 m, 3,000 kg arm that extends horizontally on top of a vertical tower. The arm extends 15 m toward

Anni [7]

Answer:

$m=18000kg$

Explanation:

From the question we are told that:

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3 years ago

Under what conditions can an object have forces acting on it, but its motion does not change ?

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Explanation: I hoped that helped!!

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3 years ago

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