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Brilliant_brown [7]
4 years ago
14

A bulb converts 9J of energy in each second from an input of 100J of energy. Calculate efficiency of this light bulb

Physics
1 answer:
77julia77 [94]4 years ago
8 0
Efficiency is calculated through dividing the actual mechanical advantage by the hypothetical mechanical advantage:

- the actual mechanical advantage is 9J because that's how much work the light bulb doing

- the hypo. mechanical advantage is 100J. Ideally, in a perfect world, the light bulb can convert 100J input into 100J output, but do to resistance and other factors it is not possible.

\frac{9}{100}  = .09
change the decimal to a percentage:

.09 = 9\%
the light bulb had 9% efficiency
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Answer:

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direction=55.52\°

Explanation:

Assuming the initial point P1 of this vector is at the origin:

P1=(X1,Y1)=(0,0)

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We can find the magnitude and direction of this vector, taking into account a vector has a initial and a final point, with an x-component and a y-component.

For the magnitude we will use the formula to calculate the distance d between two points:

d=\sqrt{{(Y2-Y1)}^{2} +{(X2-X1)}^{2}} (1)

d=\sqrt{{(28.4 m - 0 m)}^{2} +{(19.5 m - 0m)}^{2}} (2)

d=\sqrt{1186.81 m^{2}} (3)

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For the direction, which is the measure of the angle the vector makes with a horizontal line, we will use the following formula:

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