Xiaoming's family bought a new car. As shown in the figure, Xiao Ming took the car and drove at a constant speed 144km, which took 2 hours. According to the information provided in the table below,

( 1) 1.5× 10 4n 2.5× 10 5pa(2) 1. 15× 10 3n？ (3) The ground pressure is low when driving, because the roof air velocity is high and the gas pressure is low when the car is driving.

Test analysis: (1) The pressure of the car on the ground is

f = mg = 1500kg× 10N/kg = 1.5× 104n？

The pressure of the car on the ground is

(2) the speed of the car is

72 km/h = "20 m/s"

The traction of a car with P=FV at constant speed is as follows

(3) The ground pressure is low when driving, because the roof air velocity is high and the gas pressure is low when the car is driving.

Comments: This question examines the relationship between pressure, power, fluid pressure and flow. When answering, pay attention to the reading of chart information and the conversion of units.