A rock is projected from the top of a building with an initial volocity of 14.5

Question

A rock is projected from the top of a building with an initial volocity of 14.5 m/s at an angle of 57 degrees above the horizontal. The rock strikes the ground a horizontal distance of 40 m from the base of the building. assume that the ground is level and that the side of the building is vertical. how tall is the building?

Explanation / Answer

Let t be the time for which rock is in air. The ux * t = 40 => ucosA*t = 40 SO t = 5.065 seconds Now consider y direction motion The rock reaches the level it is at with a velocity uy=usinA downwards at t=uy/g =2.482 s Remaining time = 5.065-2.482=2.583 s Thus using S=ut+at^2/2 we have h=(14.5* sin57 * 2.583) + (9.8 * 2.583^2)/2 = 64.103 m Hope you like it :)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.