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A metal rod that is 4.00 m long and $\mathbf{0}\mathbf{.}\mathbf{50}\mathbf{}\mathit{c}{\mathit{m}}^{\mathbf{2}}$in cross-sectional area is found to stretch 0.20 cm under a tension of 5000 N. What is Young鈥檚 modulus for this metal?

According to the shop manual, when drilling should have a 12.7-mm-diameter in wood, plastic, or aluminum a drill should have a speed of 1250 rev/min. For a 12.7-mm-diameter drill bit turning at a constant 1250 rev/min .find

a) the maximum linear speed of any part of the bit and

The star ${\mathbf{Rho}}^{\mathbf{1}}$Cancri is 57 light-years from the earth and has a mass 0.85 times that of our sun. A planet has been detected in a circular orbit around ${\mathbf{Rho}}^{\mathbf{1}}$Cancri with an orbital radius equal to 0.11 times the radius of the earth鈥檚 orbit around the sun. What are (a) the orbital speed and (b) the orbital period of the planet of ${\mathbf{Rho}}^{\mathbf{1}}$Cancri?

Question: A stockroom worker pushes a box with mass 16.8 kg on a horizontal surface with a constant speed of 3.50m/s. The coefficient of kinetic friction between the box and the surface is 0.20. (a) What horizontal force must the worker apply to maintain the motion? (b) If the force calculated in part (a) is removed, how far does the box slide before coming to rest?

A metal rod that is 4.00 m long and $\mathbf{0}\mathbf{.}\mathbf{50}\mathbf{}\mathit{c}{\mathit{m}}^{\mathbf{2}}$in cross-sectional area is found to stretch 0.20 cm under a tension of 5000 N. What is Young鈥檚 modulus for this metal?

According to the shop manual, when drilling should have a 12.7-mm-diameter in wood, plastic, or aluminum a drill should have a speed of 1250 rev/min. For a 12.7-mm-diameter drill bit turning at a constant 1250 rev/min .find

the maximum linear speed of any part of the bit and

b) the maximum radical acceleration of any part of the bit.

鈥淎 ball is thrown from the edge of a high cliff. Regardless of the angle at which it is thrown, due to air resistance, the ball will eventually end up moving vertically downward.鈥� Justify this statement.鈥�

A gyroscope takes 3.8 s to precess 1.0 revolution about a vertical axis. Two minutes later, it takes only 1.9 s to precess 1.0 revolution. No one has touched the gyroscope. Explain.

Airports at high elevations have longer runways for take-offs and landings than do airports at sea level. One reason is that aircraft engines develop less power in the thin air well above sea level. What is another reason?

A bicycle racer is going downhill at $\mathbf{11}\mathbf{.}\mathbf{0}\mathbf{}\mathbf{m}\mathbf{/}\mathbf{s}$, when to his horror, one of his $\mathbf{2}\mathbf{.}\mathbf{25}\mathbf{-}\mathbf{kg}$wheels comes off as he is $\mathbf{75}\mathbf{.}\mathbf{0}\mathbf{}\mathbf{m}$above the foot of the hill. We can model the wheel as thin-walled cylinder $\mathbf{85}\mathbf{.}\mathbf{0}\mathbf{}\mathbf{cm}$in diameter and ignore the small mass of the spokes. (a) How fast the wheel is moving when it reaches the foot of the hill if it rolled without slipping all the way down? (b) How much kinetic energy does the wheel have when it reaches the bottom of the hill?