An object of mass m is dropped at t = 0 from the roof of a building of height h.

Question

An object of mass m is dropped at t = 0 from the roof of a building of height h. While the object is falling, a wind blowing parallel to the face of the building exerts constant force F on the object. At what time t does the object strike the ground? Express t in terms of g and h. t = Find an expression in terms of m and F for the acceleration ax of the object in the horizontal direction (taken as the positive x direction). How far is the object displaced horizontally before hitting the ground? Answer in terms of m, g, F, and h. delta x = Find the magnitude of the object's acceleration while it is falling, using the variables F, m, and g. a =

Explanation / Answer

a)

consider the motion along vertical direction

Vi = initial velocity = 0 m/s

Y = displacement = height of building = h

ay = acceleration = g

t = time taken

Using the equation

Y = Vi t + (0.5) ay t2

h = 0 t + (1/2) g t2

t = sqrt (2h/g)

b)

ax = force in X-direction / mass = F/m

c)

consider the motion along vertical direction

Vi = initial velocity = 0 m/s

X = displacement in horizontal direction

ax = acceleration = F/m

t = time taken = sqrt (2h/g)

Using the equation

X = Vi t + (0.5) ax t2

X = 0 t + (1/2) (F/m) (sqrt (2h/g))2

X = (F/2m) (2h/g)

X = Fh/mg

d)

ax = F/m

ay = g

net acceleration : a = sqrt (ax2 + ay2) = sqrt ((F/m)2 + g2)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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