<span>d = r*t
t = hours at 20 mi/hr
20t + 12*(4.5 - t) = 70
8t = 16
t = 2 hours
d at 20 mi/hr = 20*2 = 40 miles
40/20 + 30/12 = 4.5 hours
Fiora travels a total distance of 4.5 hours</span>
Answer:
No, either driver can not hear a different frequency from the other car's horn than they would if the cars were stationary.
Explanation:
Either driver hear a different frequency from the other car's horn than they would if the cars were stationary if two cars are traveling in the same direction and with the same speed along a straight highway because neither driver experiences a Doppler shift
Answer:
(B) 13.9 m
(C) 1.06 s
Explanation:
Given:
v₀ = 5.2 m/s
y₀ = 12.5 m
(A) The acceleration in free fall is -9.8 m/s².
(B) At maximum height, v = 0 m/s.
v² = v₀² + 2aΔy
(0 m/s)² = (5.2 m/s)² + 2 (-9.8 m/s²) (y − 12.5 m)
y = 13.9 m
(C) When the shell returns to a height of 12.5 m, the final velocity v is -5.2 m/s.
v = at + v₀
-5.2 m/s = (-9.8 m/s²) t + 5.2 m/s
t = 1.06 s
Beginning around 5,500 years ago, the Sumerians built cities along the rivers in Lower Mesopotamia, specialized, cooperated, and made many advances in technology. The wheel, plow, and writing (a system which we call cuneiform) are examples of their achievements.
Answer:
Balanced force
Explanation:
Balanced Forces, When forces are in balance, acceleration is zero. Velocity is constant and there is no net or unbalanced force. ... Although friction is acting on the person, there is no change in velocity and friction is not a net force in this case. Friction is only a net force if it changes the velocity of a mass.