Chapter 4.2, Problem 4.11P

A piece of metal is placed on top of a 2.0 - kg wooden block (mass density = 562 kg/m³) piece. UseArchimedes' principle to calculate the mass (in kg) of copper if the top of the wood surface is exactly at thewater's surface?

A filmmaker wants to achieve an interesting visual effect by filming a scene through a converging lens with a focal length of 50.0 m. The lens is placed betwen the camera and a horse, which canters toward the camera at a constant speed of 7.9 m/s. The camera starts rolling when the horse is 36.0 m from the lens. Find the average speed of the image of the horse (a) during the first 2.0 s after the camera starts rolling and (b) during the following 2.0 s.

Answer the question (Physics)