Here's the question you clicked on:
ksaimouli
a compact disc has a radius of 6cm if the disc rotates about its central axis at a constant angular speed of 5 rev/s what is the total distance traveled by a point on the rim of the disc 40min
when i did \[\omega=\frac{ \theta }{ t }\]
This question doesn't even require physics...it's purely mathematical: First, calculate the circumference of the circle. Then multiply that by 5 since it makes 5 revolutions per second. That will give you how far the dot traveled in 1 second. Then just multiply that times how many seconds are in 40 minutes.
Can u show me in physics way
\(\omega=\frac{ \theta }{ t }\) is ok. You should just be careful to plug in the values in the right units.
but @Vincent-Lyon.Fr i did not get the answer with this equation
Show us you numbers.
\[\theta=10\pi(2400)\]
What the question asks is the DISTANCE travelled, not the angle swept during that time.
Distance in rotation is nothing but the angle right?
No, distance is distance (in metres), and angle is angle (in radians).
so i found theta so can i use s=r theta
Yep and you should find about 4.5 km