A 100 kg football player is running down the sideline at 8 m/s and crosses the 50 yd line at the same time a 95 kg opposing team player (tackler) crosses the 50 yd line. However, the tackler is 13.7 m from the sideline. How fast must the tackler be running to catch the other player by the end zone?

Hm... I had to look for the dimensions of a football field...

Make a sketch.

The end zone is 70 yd away.

So, find the time it will take for the 100 kg football player to reach it.

Use Time = Distance/Speed

Be careful of the units. They must be the same.

Now, using Pythagoras' Theorem, we find that the distance the tackler has to run is given by:



I put the m and y where m is shows that it's 13.7 m and y meaning that it's 70 yards. Convert one into the other to find d. DO NOT calculate this directly unless the distances are in the same units.

Now that you know the distance and the time, find the speed. Post what you get! :)