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2 years ago

10

A refrigerator with a weight of 1,127 newtons needs to be moved into a house using a ramp. The length of the ramp is 2.1 meters,

and its height is 0.85 meters. What is the percentage efficiency if a force of 496 newtons is applied to the refrigerator?
A. 44 percent
B. 58 percent
C. 64 percent
D. 76 percent
E. 92 percent

2 answers:

irinina [24]2 years ago

7 0

The answer will be D. 76 percent since 496 is out of 1,127N

lina2011 [118]2 years ago

3 0

496/1127 = 0.44 = 44%

<span>sin A = 0.85/2.1. </span>
<span>A = 23.9o. </span>

<span>Fp = 1127 sin23.9 = 457 N. = Force parallel to the ramp. </span>

<span>Fn = 1127 Cos23.9 = 1,030 N. = Force </span>
<span>perpendicular to the ramp = Normal force. </span>

<span>Eff. = Fp/Fap = 457/496 = 0.92 = 92%
Correct answer: 92%</span>

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