physics. best answer=award!!?
question in picture
- WhomeLv 72 months agoFavorite Answer
Work-Energy Theorem says that the work of the force changes the kinetic energy of the mass.
FΔx = ΔKThe constant force is F = (Kf - K₀) / (xf - x₀) = (0 - 24) / (5.0 - 0) = -4.8 N
When x is -3.1 m
ΔK = FΔx
(K - 0) = -4.8(-3.1 - 5.0)
K = 38.88 J
at which time the velocity is
33.88 = ½(7.0)v²
v = ± 3.33295...
We choose the negative vector value to fit the narrative, but the request is for speed so the absolute value .
When rounded to the two significant digits of the question numerals
v = 3.3 m/s
- az_lenderLv 72 months ago
When the object passes back through x = 0, its KE will again be 24J. The dK/dx will continue to be (24J)/(-5m) as x goes from 0 to -3.1 m. When x = -1, you'll have K = 48J; when x = -2, you'll have K = 72J; when x = -3, you'll have K = 96J; when x = -3.1 m you'll have K = 98.4 J.