You've got your bicycle upside-down for repairs, with its 66-cm-diameter wheel spinning freely at 230rpm. The mass of the wheel is 1.9 kg and is concentrated mostly at the rim. You hold a wrench against the tire for 3.1s, with a normal force of 2.7N. If the coefficient between the wrench and the tire is 0.46, what is the final angular speed of the wheel?

Astudent is given an assignment to demonstrate diffraction. he takes a photograph of a straw in a glass of water. the straw appears bent at the water level. which best describes this example? a) this is a good example of diffraction. b) this is an example of dispersion and not diffraction. c) this is an example of refraction and not diffraction. d) this is an example of reflection and not diffraction.

Could someone me find the answer to this problem.

Engineers find a new metal that is stronger than steel but much lighter. this material is also significantly cheaper than what is currently used for most aircraft, available in large quantities, and easy to manufacture. the engineers are excited because this new material will lower the costs of buying and operating airplanes for companies. what is probably the best step for the engineers to make next?