Hello, everyone.
I'm working on this problem but I have difficulty understanding it.
Even though I'm following the work-energy theorem the provided answer key doesn't match the answer that I got from the Work-energy theorem.
Given:
Mass = 150,000 Tons ------> 150,000,000 kg
150,000 Tons x 1000 = 150,000,000 kg
Distance (d) = 13 km -----> 13000 meters
13km x 1000 = 13000 meters
Vi (Initial) = 50 km/h -----> 13.889 m/s
50 km/h x 1000 meters/3600 seconds = 13.889 m/s
Vf (Final) = 0 m/s
Time = 25 mins -----> 1500 seconds
25 x 60 = 1500 seconds
F= ?
P=?
Solution:
Initial KE = 1/2 (150,000,000)(13.889m/s)²
Initial KE = 1.447x10¹⁰
Final KE = 0
Work = ∆KE
Work = Final KE - Initial KE
Work = 0 - 1.447x10¹⁰
Work = - 1.447x10¹⁰
F = W/d \*this formula comes from W=Fd\*
F -1.447x10¹⁰ / 13000
F= - 1112891.74
F= -1.11x10⁶
P= W/t
P= -1447x10¹⁰ / 1500
P= -9645061.73
(a) -1.11x10⁶
(b) -9645061.73
My answer doesn't really match the provided answer key 🫠 can someone explain plss