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nevsk [136]
3 years ago
7

A good-quality measuring tape can be off by 0.42 cm over a distance of 28 m. What is its percent uncertainty? (Express your answ

er to the correct number of significant figures and proper units.)
Physics
1 answer:
Alecsey [184]3 years ago
5 0

Answer:

0.015%

Explanation:

Data provided in the question:

Length by which the measuring tape can be off, δL = 0.42 cm

Total measured length for which Error of  δL is observed, L = 28 m  

Now,  

we know,  

1 m = 100 cm  

Thus,

28 m = 28 × 100 = 2800 cm

Percent uncertainty = [δL ÷ L] × 100%

= [0.42  ÷ 2800] × 100%

= 0.015%

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To explain, I will use the equations for kinetic and potential energy:

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An object of 5 kg is moving at 5 m/s.  What is the object's kinetic energy?  (<u>answer: 5*5 = 25 J</u>)

<h3>Kinetic and Potential Energy</h3>

Sometimes, an object can have both kinetic and potential energy.  If an object is moving (kinetic energy) and is above the ground (potential), it will have both.  To find the total (mechanical) energy, you can add the kinetic and potential energies together.  An example:

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3 years ago
1. Summarize What are the four conditions of a<br>purely competitive market?​
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Answer:

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3 years ago
A long straight wire carries current to the right of the page. A rectangular loop is positioned directly under the wire in the p
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Answer:

Correct option A.

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Explanation:

The magnetic field exerts a force on a current-carrying wire in a direction given by the right-hand rule 1 (the same direction as that on the individual moving charges). This force can easily be large enough to move the wire since typical currents consist of very large numbers of moving charges.

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F = -iLB•j

Then, the force is in the negative y-direction i.e. towards the loop.

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4 years ago
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