Answer :
Answer:
Both the rocks land together.
Explanation:
Given:
initial speed of Jan, [tex]u_j=v[/tex]
initial speed of Len, [tex]u_l=2u_j=2v[/tex]
direction of velocity by Jan with respect to vertical down direction, [tex]\theta_l=0^{\circ}[/tex]
direction of velocity by Len with respect to vertical down direction, [tex]\theta_l=(90-30)^{\circ}=60^{\circ}[/tex]
Now velocity of the rock by Len in the vertically downward direction:
[tex]u_l_x=u_l.\cos\theta[/tex]
[tex]u_{lx}=2v\cos60[/tex]
[tex]u_l_x=v[/tex]
Form the equation of motion:
[tex]h=ut+\frac{1}{2} gt^2[/tex]
where:
[tex]h=[/tex] height covered by the object
[tex]u=[/tex] initial velocity of the object
[tex]g=[/tex] acceleration due to gravity
[tex]t=[/tex] time taken by the object to fall the height
Since the velocity of both the rocks is same in the vertical direction are thrown form the same height therefore both of the rocks will land together.