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masya89 [10]
3 years ago
13

The driver of a car slams on the brakes when he sees a tree blocking the road. The car slows uniformly with acceleration of -5.7

5 m/s^2 for 4.40 s, making straight skid marks 60.0 m long, all the way to the tree. With what speed does the car then strike the tree? m/s
Physics
1 answer:
Furkat [3]3 years ago
3 0

Answer:

0.99 m/s

Explanation:

t = Time taken = 4.4 seconds

u = Initial velocity

v = Final velocity

s = Displacement = 60 m

a = Acceleration = -5.75 m/s²

s=ut+\frac{1}{2}at^2\\\Rightarrow u=\frac{s-\frac{1}{2}at^2}{t}\\\Rightarrow u=\frac{60-\frac{1}{2}\times -5.75\times 4.4^2}{4.4}\\\Rightarrow u=26.29\ m/s

v=u+at\\\Rightarrow v=26.29+(-5.75)\times 4.4\\\Rightarrow v=0.99\ m/s

The car hits the tree at 0.99 m/s

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Given the the current flowing in the circuit and the elapsed time, the charge that passes through the LED is 1260 Coulombs.

<h3>What is Current?</h3>

Current is simply the rate of flow of charged particles i.e electrons caused by EMF or voltage.

If a charge passes through the cross-section of a conductor in a given time, the current I is expressed as;

I = Q/t

Where Q is the charge and t is time elapsed.

Given the data in the question;

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We substitute our given values into the expression above to determine the charge.

I = Q/t

Q = I × t

Q = 0.35A × 3600s

Q = 1260C

Therefore,  given the the current flowing in the circuit and the elapsed time, the charge that passes through the LED is 1260 Coulombs.

Learn more about current here: brainly.com/question/3192435

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Answer:

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Wood _  3/10 _0 _0.12 W/(m·K)  _0 S/m _ 4 g/cm3

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The density of the material I chose for the walls and floors for the home in Tiny World was 4 g/cm3 (Wood). I think a buildings material density is important when building homes or architectural structures because in order for that structure to stay stable the materials that are used must be dense. If the materials are not dense, the structure would most likely collapse if it is placed under too much pressure.

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