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Two pulleys having diameters of 8 inches and 12 inches respectively, are belted together. If the former makes 100 RPM how many RPM will the latter make? 10. If 5 drills cost $3.15, what is the cost of 11 of the same drills? 11. A wedge has a thickness of 1 inch at the narrow end, and a thickness of 4 inches at the wide end. If the wedge is 15 inches long, what is the taper per foot? 12. If a taper plug is 6 inches long and 2.56 inches diameter at the small end, what is the diameter at the large end if the taper is 1 inch? 13. If a 10 inch pulley makes 120RPM and is belted to another pulley which makes 96 RPM, what is the diameter of the second pulley? 14. Water pressure varies directly as the depth of the water. If the total pressure on a certain area when submerged 15 feet is 75 lbs., what will be the total pressure on the same area when it is submerged 80 feet?

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10. To find the RPM of the larger pulley, we can use the concept of belt speed, which remains constant for two pulleys connected by a belt.

The belt speed is given by the formula:

Belt Speed = Diameter of Pulley * RPM

Let's denote the RPM of the larger pulley as "x." Given that the diameter of the smaller pulley is 8 inches and its RPM is 100, we can set up the following equation:

8 inches * 100 RPM = 12 inches * x RPM

Simplifying the equation, we find:

800 = 12x

x = 66.67

Therefore, the larger pulley will make approximately 66.67 RPM.

11. To find the cost of 11 drills, we can use the concept of proportionality.

If 5 drills cost $3.15, we can set up the following proportion:

5 drills / $3.15 = 11 drills / x

Cross-multiplying and solving for x, we have:

5 * x = 11 * $3.15

x = (11 * $3.15) / 5

x = $6.93

Therefore, the cost of 11 drills is $6.93.

12. The taper of a plug is defined as the change in diameter per unit length. In this case, the taper is given as 1 inch over a length of 6 inches.

To calculate the taper per foot, we can convert the length to feet and then determine the change in diameter per foot.

1 inch taper / 6 inches length = x inch taper / 1 foot length

Cross-multiplying and solving for x, we have:

6 * x = 1

x = 1/6

Therefore, the taper per foot is 1/6 inch.

13. To find the diameter of the second pulley, we can use the concept of the speed ratio.

The speed ratio of two pulleys connected by a belt is given by the formula:

Speed Ratio = RPM1 / RPM2 = Diameter2 / Diameter1

Given that the diameter of the first pulley is 10 inches and its RPM is 120, and the RPM of the second pulley is 96, we can set up the following equation:

120 RPM / 96 RPM = Diameter2 / 10 inches

Cross-multiplying and solving for Diameter2, we have:

96 * Diameter2 = 120 * 10

Diameter2 = (120 * 10) / 96

Diameter2 ≈ 12.5 inches

Therefore, the diameter of the second pulley is approximately 12.5 inches.

14. Water pressure varies directly with the depth of the water. This means that the pressure increases linearly with depth.

If the total pressure on a certain area when submerged 15 feet is 75 lbs, we can set up a proportion to find the total pressure when submerged 80 feet.

15 feet / 75 lbs = 80 feet / x lbs

Cross-multiplying and solving for x, we have:

15 * x = 80 * 75

x = (80 * 75) / 15

x = 400 lbs

Therefore, the total pressure on the same area when submerged 80 feet would be 400 lbs.
User CamW
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Answer:

Explanation:

The cost of 11 drills with the same price would be $6.93.

User Jpavlov
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8.8k points