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soldi70 [24.7K]

3 years ago

8

A machine designed to stretch a stiff spring uses 1,550 J of energy to stretch the spring. If the work output is 1,200 J, what i

s the machine’s efficiency?

1 answer:

lapo4ka [179]3 years ago

8 0

Answer:

77%

Explanation:

efficiency= work output/work input X 100%

e = 1,200j/ 1,550 j x100%

e = 1,200/1,550= 0.77

e = 0.77 x 100%

e = 77%

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3 years ago

PLEASE HELP ASAP!!! CORRECT ANSWER ONLY PLEASE!!!

Sonbull [250]

Question 1

In order to do work, the force vector must be

in the same direction as the displacement vector and the motion.

Question 2

In which of the following cases is work being done on an object?

Pulling a trailer up a hill

Question 3

Which situation is an example of NOT doing work?

carrying a box

Question 4

Work is measured in

Joules

Question 5

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When more work was done, the couch was moved further.

Question 6

A weight lifter raises a 1600 N barbell to a height of 2.0 meters. How much work was done? W = Fd

3200 Joules

Question 7

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Question 8

Doing work at a faster rate creates power.

more

Question 9

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Question 10

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<em>*100% CORRECT ANSWERS</em>

4 0

3 years ago

If the half-life of tritium (hydrogen-3) is 12.3 years, how much of

tatyana61 [14]

Answer:

0.0000076 grams

Explanation:

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4 years ago