Iwill fail if i dont get this done, can somebody me?

You have been hired to design a spring-launched roller coaster thatwill carry two passengers per car. the car goes up a 10-m highhill, then descends 15m to the track's lowest point. you'vedetermined that the spring can be compressed a maximum o 2.0m andthat a loaded car will have a maximum mass of 400kg. for safetyreasons, the spring constant should be 10% larger than the minimumneeded for the car to just make it over the top. a) what spring constant (k) should you specify ? b) what is the maximum speed of a 350 kg car if the spring iscompressed the full amount.

What is transferred to an object when work is done

Amajor impediment to wide acceptance of electric vehicles even on the part of people who use their cars almost exclusively for commuting is the inability to use their electric vehicles for occasional extended trips. in an attempt to make purchasing electric vehicles more attractive to commuters, one electric vehicle producer is planning to offer customers three days free rental of a conventional car for every 1,000 miles that they drive their electric vehicle. which of the following, if true, most threatens the plan's prospects for success? (a) many electric vehicles that are used for commercial purposes are not needed for extended trips. (b) because a majority of commuters drive at least 100 miles a week, the cost to the producer of making good the offer would add considerably to the already high price of electric vehicles. (c) the relatively long time it takes to recharge the battery of an electric vehicle can easily be fitted into the regular patterns of car use characteristic of commuters. (d) although electric vehicles are essentially emission-free in actual use, generating the electricity necessary for charging an electric vehicle's battery can burden the environment. (e) some family vehicles are used primarily not for commuting but for making short local trips, such as to do errands.