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3 years ago

7.

Physics

2 answers:

SSSSS [86.1K]3 years ago

7 0

Free fall is a special type of motion in which the gravity is the only force that acting upon an object.

Explanation:

In the free fall the object have gravity force only. when you dropped the ball from top of the building, and it will start falling. The balls falls due to gravity. Imagine when you have held the ball in your hand, gravity is acting, but the frictional force between your fingers and ball is acting on the opposite side. When the ball is kept in air, gravity is the only force that acts on the ball. Hence in free fall, the object has no another forces except gravity.

Igoryamba3 years ago

5 0

D. Free fall

Explanation:

An object is said to be in free fall when there is only one force acting on the body, which is the force of gravity.

Near the Earth's surface, the force of gravity acting on a body is given by

F = mg

where

m is the mass of the body

g is the acceleration of gravity (its value is $9.8 m/s^2$ )

The direction of this force is downward (towards the Earth's centre).

If we apply Newton's second law on an object in free-fall, we can find its acceleration. In fact, we have:

$a=\frac{F}{m}$

And substituting F,

$a=\frac{mg}{m}=g=9.8 m/s^2$

So, every object in free-fall accelerates at $9.8 m/s^2$ towards the ground.

Learn more about free fall here:

brainly.com/question/1748290

brainly.com/question/11042118

brainly.com/question/2455974

brainly.com/question/2607086

#LearnwithBrainly

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Answer:

The answer is the 3rd option!

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2 years ago

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Maru [420]

Answer:

a) speed when Jack sees the pot : 12.92 meters per second

b) height difference 163.115 meters

Explanation:

First to calculate te initial speed we use the acceleration formula:

a= v1-v0/t

Acceleration being gravity's acceleration (9.8 m/s^2)

v1 being the speed when Jill sees the pot

v0 when Jack sees it

and t the time between

Solving for v0 it would be

v1 - a*t = v0

replacing

$58 m/s - 9.8 m/s^2 *4.6 s = v0 = 12.92 m/s$

For the second question we use the position formula setting y0 and t0 as the position and time when jack sees the pot. (and setting the positive axis downward I.E. one meter below jack would be 1m not -1m)

The formula is

$y0 + v0*t + 1/2 g *t^2 = yt$

replacing

$0m + 12.92m/s* 4.6 s + 1/2 * 9.8 m/s^2 * (4.6 s)^2 = 163.115 m$

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3 years ago

The nebular theory also predicts that the cloud should heat up as it collapses. what physical law explains why it heats up?

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3 years ago

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3 years ago

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sergiy2304 [10]

Answer:

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Explanation:

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