Answer 1

remains constant

 

For angular momentum, we have

\[\overrightarrow{L}  = m\left( \overrightarrow{r} \times \overrightarrow{v} \right)\] 

\[ \overrightarrow{v}  = v \hat i\text{ and }\overrightarrow{r}  = x \hat i + y \hat j \] 

So,\[\overrightarrow{L}  =  - mvy \hat k\]

m, v and y are constant; therefore, angular momentum remains constant.