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3 years ago

5

A 16-kg scooter is moving at a speed of 7 m/s. The scooter’s speed doubles. What is the scooter’s kinetic energy when its speed

doubles?
a. 784 J
b. 1568 J
c. 392 J
d. 112 J

1 answer:

lbvjy [14]3 years ago

5 0

The formula for kinetic energy is:

KE = 0.5mv^2

where:
m = mass
v = speed

Given this formula, the original KE of the scooter is calculated as 392 J. Since the speed is doubled, it can be observed in the formula that the change would actually affect the kinetic energy by quadrupling it. This is because 2^2 is 4. So, 392(4) = 1568 J or B.

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Answer:

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Explanation:

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According to the laws of friction,

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μ = 0.31

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2 years ago

What is the relationship between the strength of an

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Answer:

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N = Number of turns of the coil

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3 years ago

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3 years ago

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klemol [59]

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What is written above is expressed mathematically as follows:

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Where:

$F_{E}=60 N$ is the electrostatic force

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$q_{1}$ and $q_{2}$ are the electric charges

$d=3 m$ is the separation distance between the charges

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$60 N= 8.99(10)^{9} Nm^{2}/C^{2}\frac{q_{1}.q_{2}}{(3 m)^{2}}$ (2)

Isolating $q_{1}$ and $q_{2}$ :

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Now, if we keep the same charges but we decrease the distance to $d_{1}=1 m$ , (1) is rewritten as:

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Then, the new electrostatic force will be:

$F_{E}= 539.4 N$ (5) As we can see, the electrostatic force is increased when we decrease the distance between the charges.

4 0

3 years ago