The loaded trailer has a mass of 800 kg with center of mass at G and is attached at A to a rear-bumper hitch. If the car and trailer reach a velocity of 48 km/h on a level road in a distance of 39 m from rest with constant acceleration, compute the vertical component Ay of the force supported by the hitch at A. The vertical force Ay is positive if up, negative if down. Neglect the small friction force exerted on the relatively light wheels.

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.

Which of the choices below is one of the primary gases found in the atmosphere? a. helium b. carbon dioxide c. nitrogen d. argon

In order of decreasing light-transmitting capabilities of materials, which is the correct sequence? a. transparent -> translucent -> opaque b. opaque -> transparent -> translucent c. opaque -> translucent -> transparent d. translucent -> transparent -> opaque