motor efficiency

[searley]

help. if a motor`s input is 75w and it`s output is 50w.what will the motor`s efficiency be ?i was trying 75/50 and getting 1.5 but the answer is 33.3%.

see i do need help.cheers.

 

[Theorysparky]

efficiency= Pout/Pin

http://www.engineeringtoolbox.com/electrical-motor-efficiency-d_655.html

from your posts during the day it seems you are doing lots of sample questions

i typed in 'electrical formula' on a search engine

and found loads of sites which would help,,,,,,,just a thought while waiting for us lot

 

[Theorysparky]

help. if a motor`s input is 75w and it`s output is 50w.what will the motor`s efficiency be ?i was trying 75/50 and getting 1.5 but the answer is 33.3%.see i do need help.cheers.

are you sure that is right ,,the answer ???

 

[Apache]

Apache makes it 66%. If you've managed to make one >100% can you PM me the plans

How exactly is the question worded? Does it ask what the efficiency is OR what is lost.

 

[DTIL]

Apache makes it 66%. If you've managed to make one >100% can you PM me the plans How exactly is the question worded? Does it ask what the efficiency is OR what is lost.

Exactly my thoughts

Power out/Power in = efficiency

Therefore 50/75 = 0.66 recurring (or 66%)

If they are asking for power lost, then it would equate to around 33% (rounding up/down)

 

[searley]

i worded it the way it is on the paper i was getting 66%.close to throwing calculater out the window.

 

[Apache]

Answers can be wrong in the books

 

[binky]

i worded it the way it is on the paper i was getting 66%.close to throwing calculater out the window.

My experience of C&G courses is that they are strewn with errors