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3 years ago

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After a while, the car started to go around a long bend, still maintaining its constant speed of 55 miles per hour. Is there a n

et (unbalanced) force acting on the car? 1. No; the speed of the car does not change. 2. Cannot be determined 3. No; the velocity of the car does not change. 4. Yes; its direction is not the same as the velocity. 5. Yes; its direction is the same as the velocity.

1 answer:

sukhopar [10]3 years ago

6 0

Answer:

4) True. The change of direction needs an unbalanced force

Explanation:

Let us propose the resolution of the problem using Newton's second law.

F = m a

As the car is spinning the acceleration is centripetal

a = v2.r

F = m v2 / r

We can see that as the velocity of a vector even if its module does not change, the change of direction requires an external force.

Now we can analyze the statement if they are true or false

1) and 3) False, even when the speed changes, the direction changes

2) False with the speed change can be determined

4) True. The change of direction needs an unbalanced force

5) False are different things. the direction is where it is going and the speed is the magnitude of the vector

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f=μ*N the friction force is equal to coefficient of static friction multiply the normal force (m*g).

f=m.a=μ*N= m*a= μ*m*g= m*a

then

a=μ*g=0.32*9.8m/s^2= 3.14 m/s^2

With this value we can determine the short distance to stop the train

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irinina [24]

Answer:

1.24 m/s

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Metric unit conversion:

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Marrrta [24]

Our values can be defined like this,

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$W = \Delta KE$

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KE = Kinetic energy,

Given things like that and replacing we have that the work is given by

W = Fd

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So,

$Fd = \frac {1} {2} m ^ 2$

Clearing F,

$F = \frac {mv ^ 2} {2d}$

Replacing the values

$F = \frac {(65) (3.5)} {2 * 0.55}$

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erastova [34]

Answer:

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Arrhythmias can be categorized as heart block, bradycardia, tachycardia, fibrillation, flutter, sick sinus syndrome, and is diagnosed by Electrocardiography.

In Flutter, the heart chambers do get sufficient time to get filled with blood completely prior to next contraction.

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