Question 129: Motion in 2D & Vectors

Question

A boy can throw a stone up to a maximum height of 10 m. The maximum horizontal distance that the boy
can throw the same stone up to will be

Accepted Answer

We know, $$R = {{{u^2}{{\sin }2}	heta } \over g}$$ and $$H = {{{u^2}{{\sin }^2}	heta } \over {2g}};$$
$${H_{\max }}\,\,$$ is possible when $$	heta  = 90$$$$^\circ $$
$${H_{\max }} = {{{u^2}} \over {2g}} = 10 \Rightarrow {u^2} = 10g 	imes 2$$
As $$R = {{{u^2}\sin 2	heta } \over g}$$
Range is maximum when projectile is thrown at an angle $$45^\circ $$.
$$ \Rightarrow {R_{\max }} = {{{u^2}} \over g}$$
$${R_{\max }} = {{10 	imes g 	imes 2} \over g} = 20$$ meter

Answer

$$20\sqrt 2 $$ m

Answer

10 m

Answer

$$10\sqrt 2 $$ m

Answer

20 m

Motion in 2D & Vectors

A boy can throw a stone up to a maximum height of 10 m. The maximum horizontal distance that the boy can throw the same stone up to will be

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