Question$-1$

An elevator is moving upward at a constant speed of $4\frac{m}{s}.$ A man standing $10$ m above the top of the elevator throws a ball upward with a speed of $3\frac{m}{s}.$ The ball undergoes uniformly accelerated motion. Determine

The acceleration of the ball $(a_{\text{B}\text{a}\text{l}\text{l}})=-9\mathrm{.}81m{s}^{-2}$

The acceleration of the elevator $(a_{\text{E}\text{l}\text{e}\text{r}\text{a}\text{t}\text{o}\text{r}})=0$

When $(t)$ the ball hits the elevator $($i$.$e$.Y_{\text{B}\text{a}\text{n}}=Y_{\text{E}\text{l}\text{e}\text{v}\text{e}\text{a}\text{t}\text{o}\text{r}})$

Where the ball will hit the elevator with respect to the man's location $($i$.$e$.Y_{\text{b}\text{a}\text{t}})$

Verify that $Y_{\text{B}\text{a}\text{l}\text{l}}=Y_{\text{E}\text{l}\text{e}\text{v}\text{e}\text{a}\text{t}\text{o}\text{r}}$

Hint Place the origin of the position coordinate at the level of the standing man, the positive direction