A car drives from the top of the slope to the bottom of the slope at a constant speed along a slope with a slope ratio of 1 ∶ 3. The vertical distance from the top to the bottom of the slope is known to be 100 m, and the speed of the car is 30 km / h. The process of calculating the time (accurate to 1 s) required for the car from the top to the bottom of the slope is obtained

A car drives from the top of the slope to the bottom of the slope at a constant speed along a slope with a slope ratio of 1 ∶ 3. The vertical distance from the top to the bottom of the slope is known to be 100 m, and the speed of the car is 30 km / h. The process of calculating the time (accurate to 1 s) required for the car from the top to the bottom of the slope is obtained

38 seconds
t=s/v
s=100x(1x1+3x3)=316.23m
v=30km/h=30x1000/3600=8.33m/s
t=37.96s=38s

A 5000kg car is driven up the slope with a length of 100m and a height of 10m. The speed of the car is 10m / s before going up the slope and 5m / s at the top of the slope,
The friction force and air resistance are 0.05 times of the vehicle weight?

∵ 2As = VT ^ 2-v0 ^ 2 ∵ a = (VT ^ 2-v0 ^ 2) / 2S = ((10m / s) ^ 2 - (5m / s) ^ 2) / 2 × 10m = 3.25m ^ 2 / s ∵ f = ma = 5000kg × 3.25m ^ 2 / S = 16250nf resistance = 0.05g = 0.05mg = 0.05 × 5000kg × 9.8n/kg = 2450nf traction = F + F resistance = 16250n + 2450n = 18700n