Answer:
Toyota Camry
F_d = 51.852 N
F_d = 100.042 N
Hummer H2
F_d = 412.0888 N
F_d = 8351.755 N
Explanation:
Given:
- The density of air p_air = 1.2 kg/m^3
- The drag force equals car's engine force.
Find:
- What are the drag forces in newtons at 80 km/h and 105 km/h for a Toyota Camry? (Drag area = 0.70 m2 and drag coefficient = 0.28.)
- What are the drag forces in newtons at 80 km/h and at 105 km/h for a Hummer H2? (Drag area = 2.44 m2 and drag coefficient = 0.57.)
Solution:
- The formula for drag force is given as follows:
F_d = 0.5*C_d*p_air*A*V^2
Where,
A : The drag Area m^2
C_d: The drag coefficient
V: Velocity m/s
a) Toyota Camry
C_d = 0.28 , A = 0.70 m^2 , V = 80 km/h = 22.222 m/s
Then compute the F_d drag force:
F_d = 0.5*0.28*1.2*0.70*(22.22)^2
F_d = 51.852 N
C_d = 0.28 , A = 0.70 m^2 , V = 105 km/h = 29.1667 m/s
Then compute the F_d drag force:
F_d = 0.5*0.28*1.2*0.70*(29.1667)^2
F_d = 100.042 N
b) Hummer H2
C_d = 0.57 , A = 2.44 m^2 , V = 80 km/h = 22.222 m/s
Then compute the F_d drag force:
F_d = 0.5*0.57*1.2*2.44*(22.22)^2
F_d = 412.0888 N
C_d = 0.28 , A = 0.70 m^2 , V = 105 km/h = 29.1667 m/s
Then compute the F_d drag force:
F_d = 0.5*0.57*1.2*2.44*(29.1667)^2
F_d = 8351.755 N
