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Question:

how do i do this math problem?

i have no idea how to do these math problems please help me if you can and show your work1. An electric hoist is used to lift a piece of equipment 2 ft. The diameter of the drum on the hoist is 10 inches. Find the number of degrees through which the drum must rotate.2. A car is moving at a rate of 40 miles per hour; and the diameter of its wheels is 2.5ft a. find the number of revolutions per minute the wheels are rotatingb. find the angular speed of the wheels in radains per minute

Answer:

1. 2ft = 24in 10in * pi = 31.416in circumference To lift the object 24in, it must wrap around the hoist 24in If it was to wrap around 31.416in, the it would revolve once, thus being 360 degrees, although it only needs to go around 24in 24/31.416 * 360 2. a. 40*5280/60/(2*pi) b. ans of a * 2pi
1. 2x12=24ft 24/(2*pi*10) = 1/pi = 0.3 turns = 0.3*360 = 108 degrees 2. 40 mph = 40 * 5280 / 60 ft / min = 3520 ft / min 2pir = pi *d = pi * 2.5 3520/(2.5*pi) = 448 rev/min 448 * 2*pi = 2816 rad/min

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