a snake is come toward you at 1.5 m/s. if you start walking when its 5 m away how fast must you go so that snake dont over take you when have gone 100 m?

Question

a snake is come toward you at 1.5 m/s.  if you start walking when its 5 m away how fast must you go so that snake dont over take you when have gone 100 m?

anonymous · Answer

I like to set these problems up with a system of equations.  So both of you will be traveling at constant velocities, so we can use the average velocity definition to solve this:
$$V=\frac{\Delta X }{ \Delta t }$$

Now we can think about setting this up for the snake to catch you, and then any velocity greater than that would have you stay clear.

The problem states you will walk 100m.  If the snake catches you, it will have to go that some 100m + the 5m it was behind to begin with.  So we get the following expressions:

You:   $$V = \frac{ 100 }{ \Delta t}$$
snake: $$1.5 = \frac{ 105 }{ \Delta t }$$

The key to solving now is realizing that you were both traveling for the same amount of time.  So, solve each equation for delta t and set them equal to solve for your velocity V.