Answer:
4 stations
Step-by-step explanation:
If we need to be at least 98% certain that an enemy plane flying over will be detected by at least one station, we must ensure that there is at most a 2% chance that no radar stations detect the plane.
The probability that a single radar station does not detect the plane is 0.35.
For n radar stations:
Rounding up to the next whole station, at least 4 stations are needed.
Answer:
a) 3 inch pulley: 11,309.7 radians/min
6) 6 inch pulley: 5654.7 radians/min
b) 900 RPM (revolutions per minute)
Step-by-step explanation:
Hi!
When a pulley wirh radius R rotantes an angle θ, the arc length travelled by a point on its rim is Rθ. Then the tangential speed V is related to angular speed ω as:
When you connect two pulleys with a belt, if the belt doesn't slip, each point of the belt has the same speed as each point in the rim of both pulleys: Then, both pulleys have the same tangential speed:
We need to convert RPM to radias per minute. One revolution is 2π radians, then:
The saw rotates with the same angular speed as the 6 inch pulley: 900RPM