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The resistance of bicycles running at normal speed on straight roads is about 0.02 times of the total weight of bicycles and people, and the power of cyclists is the closest to () A. 10WB. 100WC. 1 kWD. 10 kW
Suppose the mass of the person and the car is 70kg, the gravity is 700n, then the resistance is 14N. Suppose the speed of the bicycle is 10m / s, then the power of the cyclist is p = FV = FV = 14 × 10W = 140W, which is the closest to 100W
The resistance of bicycles running at normal speed on straight roads is about 0.02 times of the total weight of bicycles and people, and the power of cyclists is the closest to ()
A. 10WB. 100WC. 1 kWD. 10 kW
Suppose the mass of the person and the car is 70kg, the gravity is 700n, then the resistance is 14N. Suppose the speed of the bicycle is 10m / s, then the power of the cyclist is p = FV = FV = 14 × 10W = 140W, which is the closest to 100W
The vehicle with mass m runs on a flat and level road with constant power P
When the speed of the car is V2 (V2, V1), the acceleration of the car is?
p=F1*v1
f=F1
p=F2*v2
F2-f=ma
yes
a=(v1-v2)*p/(v1*v2)
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