Question

Are these the correct answers for these problems?

Calculate the efficiency of a person who is able to do 40 J of work by putting in 110 J of energy. Round the answer to the ones place and include the correct symbol for the unit of the answer.



4.


Calculate the efficiency of a machine that is able to do 75 J of work when 165 J of energy is added to it. Round the answer to the ones place and include the appropriate symbol with the answer.



5.


If a person is 67% efficient in lifting an object, how much work was done when the person input 130 J of energy?

Answer 1

36.4, 45.5, 51.5, 89.2

Answer 2

I have the answers but I need to know if they're right

Answer 3

You have posted 4 answers for 3 problems. I agree with the first two answers.

Answer 4

It's the last 2 that I don't know is correct

Answer 5

How many problems did you post?

Answer 6

all of them

Answer 7

Look at your post. How many problems are posted there?

Answer 8

2 are posted but I have the right answers for the 1st 2 it's the last 2 that I need help bwith

Answer 9

the last 2 answers are 51.5 and 89.2

Answer 10

YOU HAVE ONLY POSTED 3 PROBLEMS. HOW IS SOMEONE SUPPOSED TO HELP YOU WITH 4 PROBLEMS IS YOU HAVE ONLY POSTED THREE PROBLEMS?????

Answer 11

If a person is 67% efficient in lifting an object, how much work was done when the person input 130 J of energy? This answer should be rounded to the ones place. It also needs to include the appropriate unit with the answer.



6.


A person is 67% efficient. If they are able to do 75 J of useful work, what is their total work or energy input? Round your answer to the tens place. Be sure to include the appropriate unit in the answer.

Answer 12

those are the questions

Answer 13

If a person is 67% efficient in lifting an object, how much work was done when the person input 130 J of energy? This answer should be rounded to the ones place. It also needs to include the appropriate unit with the answer.
.67=x/130

Answer 14

A person is 67% efficient. If they are able to do 75 J of useful work, what is their total work or energy input? Round your answer to the tens place. Be sure to include the appropriate unit in the answer.
.67=75/x

Answer 15

I tried to divide but I think i'm wrong

Answer 16

do you how to solve them

Answer 17

Do you know the formula for calculating efficiency? We should start with that...

Answer 18

Yea but I don't think I have the right answers

Answer 19

\[E_{ff}=\frac{output}{input}\]Plugging in the values you were given you have:\[0.67=\frac{output}{130J}\]Now you just need to solve for output.

Answer 20

Is the output the answer when you divide 67 by 130

Answer 21

You need to take the equation above and isolate the output to one side...that doesn't involve division :)

Answer 22

If a person is 67% efficient in lifting an object, how much work was done when the person input 130 J of energy? This answer should be rounded to the ones place. It also needs to include the appropriate unit with the answer.

.67=x/130

x=.67(130)=87.1

Answer 23

Sorry @Mertsj, didn't know you were still helping

Answer 24

Well I need all the help I can get so thanks to both of you

Answer 25

A person is 67% efficient. If they are able to do 75 J of useful work, what is their total work or energy input? Round your answer to the tens place. Be sure to include the appropriate unit in the answer.

.67=75/x

.67x=75

x=75/.67
x= 111.9

Answer 26

@Shane_B No problem. I didn't know that the asker did not know how to solve algebra 1 equations.

Answer 27

Both answers involve simply using the efficiency formula and solving for a single unknown value...as @Mertsj is showing you

Answer 28

I see them and yes I have a tough time with math

Answer 29

Thanks @Shane_B and @Mertsj