You are asked to design a new type of loop-the-loop ride. instead of rolling down a long hill to generate the speed to go around the loop, the 310 kg cart starts at rest(with two passengers) on a track at the same level as the bottom of the 9.6 m radius loop. the cart is pressed against a compressed spring that, when released, launches the cart along the track around the loop.

part a

choose a spring of the appropriate spring constant to launch the cart so that the downward force exerted by the track on the cart as it passes the top of the loop is 0.2 times the force that earth exerts on the cart. the spring is initially compressed 6.0 m .

express your answer to two significant figures and include the appropriate units.

1. what is the relationship between wavelength and the penetrating power of an electromagnetic wave? a) the penetrating power has no relationship to the wavelength. b) the penetrating power increases as the wavelength increases. c) the penetrating power decreases as the wavelength increases. d) the penetrating power decreases as the wavelength decreases. 2. as ice melts and turns into water, the speed of sound through the material would most likely do what? justify your answer. a) the speed would not change because the material is always water. b) the speed of sound would increase because the density of water is less than that of ice. c) the speed of sound would increase because energy is added to ice in order to make it melt. d) the speed of sound would decrease because sound travels faster through solids than liquids. 3.which of these waves need a medium to travel through? a) sound b) x-rays c) infrared rays d) visible light