A six-pole three-phase squirrel-cage...

Question 1 / 270705eccefa4bacbc34ba4d48220

Question 1 of 270705eccefa4bacbc34ba4d48220

A six-pole three-phase squirrel-cage induction motor operating at 60 Hz is running at 1155 rpm. What is the percentage slip in this case?

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Question 1 of 27070

Q

A six-pole three-phase squirrel-cage induction motor operating at 60 Hz is running at 1155 rpm. What is the percentage slip in this case?

🔍 Key Concepts

• Synchronous speed of an induction motor and how to calculate it using frequency and number of poles • Definition of slip in an induction motor as a ratio or percentage • How to convert a slip ratio into percentage slip

💭 Think About

• First, compute the motor’s synchronous speed based on 60 Hz and 6 poles. Is the running speed higher or lower than this value? • Determine the difference between synchronous speed and actual speed, then compare that difference to synchronous speed. • After you find the slip as a decimal, think about how to express it as a percentage and which choice matches most closely.

✅ Before You Answer

• Confirm you are using the correct formula: Ns = 120 × frequency / number of poles for synchronous speed in rpm. • Make sure slip is calculated as (Ns − N) / Ns, not the other way around. • Double‑check your final number: did you convert the decimal slip to percent before comparing to the answer choices?

Question 1 of 27070

Q

A six-pole three-phase squirrel-cage induction motor operating at 60 Hz is running at 1155 rpm. What is the percentage slip in this case?

A

0.03

B

0.0375

C

0.0425

D

0.05

Question 1 / 270705eccefa4bacbc34ba4d48220

Question 1 of 270705eccefa4bacbc34ba4d48220

A six-pole three-phase squirrel-cage induction motor operating at 60 Hz is running at 1155 rpm. What is the percentage slip in this case?

Back

Question 1 of 27070

Q

A six-pole three-phase squirrel-cage induction motor operating at 60 Hz is running at 1155 rpm. What is the percentage slip in this case?

🔍 Key Concepts

• Synchronous speed of an induction motor and how to calculate it using frequency and number of poles • Definition of slip in an induction motor as a ratio or percentage • How to convert a slip ratio into percentage slip

💭 Think About

• First, compute the motor’s synchronous speed based on 60 Hz and 6 poles. Is the running speed higher or lower than this value? • Determine the difference between synchronous speed and actual speed, then compare that difference to synchronous speed. • After you find the slip as a decimal, think about how to express it as a percentage and which choice matches most closely.

✅ Before You Answer

• Confirm you are using the correct formula: Ns = 120 × frequency / number of poles for synchronous speed in rpm. • Make sure slip is calculated as (Ns − N) / Ns, not the other way around. • Double‑check your final number: did you convert the decimal slip to percent before comparing to the answer choices?