Calculating Net Force for a Car in Motion
Initial velocity (u) = 0 km/h
Final velocity (v) = 45.0 km/h
Distance (s) = 90 m = 0.09 km
Using the equation of motion: (v² - u²) = 2as, we can find the acceleration (a).
Substitute the values: (45.0 km/h)² - 0² = 2a(0.09 km)
Solve for acceleration (a):
a = (45.0 km/h)² / (2 * 0.09 km) = 11,250 km/h²
Ignoring friction, the net force acting on the car points in the direction of its movement. According to Newton's second law, the net force (F) is equal to the mass (m) multiplied by the acceleration (a).
Given that the mass of the car is 4500 kg, we can calculate the net force:
F = (4500 kg) * (11,250 km/h²)
Since 1 N = 1 kg*m/s², we need to convert the acceleration to meters per second squared (m/s²).
Converting acceleration: 11,250 km/h² = (11,250 km/h²) * (1000 m/km) * (1/3600 h/s)² ≈ 0.868 m/s²
Therefore, the net force acting on the car is:
F = (4500 kg) * (0.868 m/s²) ≈ 3906.25 N ≈ 3900 N