A 4500 kg car accelerates from rest to 45.0 km/h over a distance of 90 m. Find the net force
acting on the car.

please help

The car undergoes an acceleration a such that

(45.0 km/h)² - 0² = 2 a (90 m)

90 m = 0.09 km, so

(45.0 km/h)² - 0² = 2 a (0.09 km)

Solve for 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 (it's also pulled down by gravity, but the ground pushes back up). Newton's second law then says that the net force F is equal to the mass m times the acceleration a, so that

F = (4500 kg) (11,250 km/h²)

Recall that Newtons (N) are measured as

1 N = 1 kg • m/s²

so we should convert everything accordingly:

11,250 km/h² = (11,250 km/h²) (1000 m/km) (1/3600 h/s)² ≈ 0.868 m/s²

Then the force is

F = (4500 kg) (0.868 m/s²) = 3906.25 N ≈ 3900 N

the focus of lesson 1 is newton's first law of motion - sometimes referred to as the law of inertia. newton's first law of motion is often stated as. an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

explanation: