Question: Suppose we have a tyre hanging in mid air and has a metal rod in the middle of the tyre. If we apply a force at the end of the tyre then a Torque will be produced.
I heard from someone that if we apply force at the end of it(the tyre) then there will be an increase in angular momentum in direction perpendicular to both the force and the moment arm.

So, **my question is:**
What does the term "there will be an increase in angular momentum in directon perpendicular to both the force and the moment arm" means and what will it be beneficial of?

Answer: 
velocity of dog after jumping from the boat is *3m/s*, since it already had a velocity of *1m/s* and another *2m/s* relative to the boat. Change the expression of velocity of dog wrt ground as $v\_{dg}=v\_{db}+v\_{bg}$ (*velocity of dog wrt ground= velocity of dog wrt boat+velocity of boat wrt ground*)

*Initial momentum = final momentum in the direction in which there is no force....*

$(5+20)$*($1m/s$) = $5$*($3m/s$) + $20$\*($x$ $m/s$)
Your answer is wrong as ,if you are performing all calculations w.r.t. ground then you also need to take the velocity of dog w.r.t. ground which would be 3m/s as the boat is already moving with a velocity of 1m/s w.r.t. ground and dog has jumped from the boat with velocity 2m/s w.r.t. the boat therefore the velocity of dog w.r.t. ground will be 3m/s , if you take this value in your calculations then you will get the velocity of boat as 1/2 m/s .