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The angular speed of a flywheel is increased from 600 rpm to 1200 rpm in 10 s. The number of revolutions completed by the flywheel during this time is:

Asked in NEET 2026 · Equations of rotational motion

• (1) 900
• (2) 600
• (3) 150
• (4) 300

Step-by-step solution

Why the other options are wrong

• (1) comes from is the mean angular speed in rpm, (600+1200)/2=900, read off as a count of revolutions instead of a rate
• (2) comes from is the change in angular speed, 1200-600=600 rpm, read off as a count
• (4) comes from adding the two speeds instead of averaging them: (600+1200)/(60)=30 rev s⁻¹ over 10 s gives 300

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