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The minute hand of a certain clock is 6 in long. Starting from the moment when the hand is pointing straight up, how fast is the area of the sector that is swept out by the hand increasing at any instant during the next revolution of the hand? NOTE: Enter the exact answer. Rate of the area change = ____ in²/min

User PhilW
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Final answer:

The rate at which the area of the sector swept out by the 6-inch long minute hand of a clock is increasing at any instant is 6π in²/min.

Step-by-step explanation:

The student has asked how fast the area of the sector that is swept out by the minute hand of a clock increases at any instant during the next revolution of the hand, given that the minute hand is 6 inches long.

To find this, it's essential to understand the formula for the area of a sector of a circle:

Area of sector = (1/2)·r^2·θ, where r is the radius and θ is the central angle in radians. Since the minute hand completes a full revolution in 60 minutes, the angle θ covered by the minute hand per minute is 2π radians/60 minutes = π/30 radians per minute.

To calculate the rate of area change, we differentiate the area of the sector with respect to time t, which gives us d(Area)/dt = (1/2)·r^2·(dθ/dt).

Plugging in the values, we get d(Area)/dt = (1/2)·(6 inches)^2·(π/30 radians/minute) = 6π in²/min.

User Vinay Shetty
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