Vectors Pt. 6(b.): Resultant Velocities Word Problem

Hello all,

Here we will look into a word problem that requires us to find a new velocity based on a few stated criteria. This W.P. (word problem) is an idealized situation and does not contain all of the real world factors for solving but we can still see some useful data. As always If you need any clarifications or see any mistakes please correct me.



  1. In the table below we break down all of the hypothesized factors and the links provide more detailed information for each one. Some factors are obviously shared with other types of endangered species on our planet and are part of to the worldwide biodiversity crisis such as habitat destruction, alteration and fragmentation (Fisher and Shaffer 1996, Davidson et al. 2001, Marsh and Trenham 2001), introduced species (Vredenburg 2004, Kats and Ferrer 2003) and over-exploitation (Jennings and Hayes 1985, Lannoo et al. 1994). For these threats, we have a pretty good understanding of the ecological mechanisms underlying declines (Collins and Storfer 2003). However, amphibians have also declined in relatively ‘pristine’ and protected environments (Wake 1991, Crump et al. 1992, Lips 2000). These more complex and elusive mechanisms include climate change (Pounds et al. 1999, Kiesecker et al. 2001, Carey and Alexander 2003), increased UV-B radiation , chemical contaminants (Hayes et al. 2002, Blaustein et al. 2003), emerging infectious diseases (Daszak et al. 2003; see AmphibiaWeb’s global distribution map of chytrid) and deformities (or malformations) . The underlying mechanisms behind these factors are complex and they may be working synergistically with more straight forward factors, such as habitat destruction and introduced species, to exacerbate declines (Kiesecker et al. 2001, Blaustein and Kiesecker 2002). Researchers are finding that there is not a single overarching cause for global declines, instead all of these factors are threatening amphibian populations and the threat tends to vary depending on the location. If we are going to prevent further extinctions, research must move forward quickly and be used effectively in management by governments and non-governmental organizations around the world.

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