Respuesta :
Answer:
Speed = 72.76mph
Explanation:
east direction signifies +
Therefore,
1515E -1125(45) = -2640
F = -2640×0.75 = -1980lbs
so,
-1980lbs = Ma
but m = 2640×g where g = 32.2 ft/s²
so,
a = -(1980/2640g) = -0.75×g = -24.15ft/s² = dv/dt
0 = V-24.15t
V =24.15t
22.5 = Vt -12.07t²
22.5 = 24.15t² - 12.07t² = 12.07t²
t = 1.37 seconds
Therefore,
V = 24.15 × 1.37 seconds = 33.1 ft/s
converting to mph gives
33.1 ft/s = 22.6 mph
now back to momentum
1515 E -1125(45) = 2640 V
1515 E = 50625+59664
Speed = 72.76 mph
Answer:
72.8mph
Explanation:
east is positive
1515 E -1125(45) = 2640 V
F = 2640*.75 = -1980 pounds
so
-1980 pounds = m a
but m = 2640/g where g = 32.2 ft/s^2
so
a = -(1980/2640)g = -.75 g = -24.15 ft/s^2
= dv/dt
0 = V-24.15 t so V =24.15 t
22.5 = V t -12.07 t^2
22.5 = 24.15 t^2 - 12.07 t^2 = 12.07 t^2
t = 1.37 seconds
so
V = 24.15 * 1.37 seconds = 33.1 ft/s
convert that to mph
33.1 ft/s = 22.6 mph
now back to momentum
1515 E -1125(45) = 2640 V
1515 E = 50625+59664
E = 72.8 mph