Suppose a spring has a relaxed length of 25.1 cm. The simulation refers to this as the natural length. This is the length of the spring when it is not stretched nor compressed by any force. When you hang a mass of 250 g on the vertical spring, the spring stretches to a new length of 33.9 cm. What is an estimate of the spring constant, k, of the spring? (Enter your answer in N/m.) Measuring only one value is not a good way to get the value, but you can an idea of the approximate size.

Which describe reflection? check all that apply. light bounces off a boundary.

Follow these directions and answer the questions. 1. set up the ripple tank as in previous investigations. 2. bend the rubber tube to form a "concave mirror" and place in the ripple tank. the water level must be below the top of the hose. 3. generate a few straight pulses with the dowel and observe the reflected waves. do the waves focus (come together) upon reflection? can you locate the place where the waves meet? 4. touch the water surface where the waves converged. what happens to the reflected wave? 5. move your finger twice that distance from the hose (2f = c of c, center of the curvature) and touch the water again. does the image (the reflected wave) appear in the same location (c of c)? you may have to experiment before you find the exact location. sometimes it is hard to visualize with the ripple tank because the waves move so quickly. likewise, it is impossible to "see" light waves because they have such small wavelengths and move at the speed of light. however, both are examples of transverse waves and behave in the same way when a parallel wave fronts hit a curved surface.

Aman throws a football straight into the air. as it rises, it slows down. which type of energy is the football gaining?