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3 years ago

13

Tracy stands on a skateboard and tosses her backpack to her friend who is standing in front of her. Which best describes the acc

eleration Tracy experiences?
It is less than the acceleration of the backpack because she has a greater mass.
It is greater than the acceleration of the backpack because she has a greater mass.
It is less than the acceleration of the backpack because she uses a smaller force.
It is greater than the acceleration of the backpack because she uses a larger force.

1 answer:

madreJ [45]3 years ago

5 0

Answer:

A

Explanation:

It is less than the acceleration of the backpack because abs has a greater mass.

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The speed decreases.

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where $m_{1}$ is the initial mass of the train, and $v_{1}$ the initial speed of the train.

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3 years ago

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Answer:

A.) The arrow`s range is 624,996 m

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Explanation:

We have a case of oblique movement. In these cases the movement in the X axis is a Uniform Rectelinear Movement (URM), and a Uniform Accelerated Movement (UAM) in the Y axis.

By the way, the equations that we use for the X axis will be from URM, and those for the Y axis wiil be from UAM.

<u>Equations</u>

X axis:

$X=v_{ox}*t$

$v_{0x} =v_0cos(\alpha)$

Y axis:

$Y= Y_0 +v_{y0} t - \frac{g}{2} t^2$

A.) First, it is necessary to know t, total time.

To figure out t value, we use UAM, since time is determined by this movement.

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$0= Y_0 +v_{y0} t - \frac{g}{2} t^2$

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Caculate the segcond degree equation to obtain the two possible values for t:

$t_1= 10.18 \\t_2= -0.04046$

But, in physics, time it could not be negative, so we take $t_1= 10.18$

Caculate now:

$X=79m/s*cos(\39)*10.18s= 624.996 m$

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Using the same procedure that item A, caculate X

First, we need to know the new time

$0=2.4m+92m/s*sin(39)t-(1/2*9.81m/s^2)t^2$

And we obtain:

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Finally:

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