1(ke, pe) an object of mass 90 lbm is projected straight upward from the surface of the earth and reaches a height of 900 ft when its velocity reaches zero. the only force acting on the object is the force of gravity. the acceleraton of gravity is g = 32.2 ft/s2 . determine the initial kinetic energy of the object [ft·lbf], and the object’s initial velocity [ft/s].

Initial kinetic energy will be 2608200 lbf-ft

Initial speed will be 240.7488 m/sec                

Explanation:

We have given height h = 900 ft

Mass of the object m = 90 lbm

Acceleration due to gravity

Initial kinetic energy will be equal to potential energy of the object

So kinetic energy = potential energy = mgh

This energy is also equal to the initial kinetic energy

So

So initial velocity will be 240.7488 m/sec

ι вєℓιєνє ιт ιѕ тнє fιяѕт ¢нσι¢є(α.)

нє ѕнσυℓ∂ ѕмιℓє ρσℓιтℓу αи∂ ѕρєαк тσ тнє ρєяѕσи ωнσ ιѕ ιитєяяυριиg αfтєя тнє ∂ιѕ¢υѕѕισи

нσρє ι ¢συℓ∂ нєℓρ.

the area between the graph and the t axis