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The friction resistance of a truck with a mass of 8t is 0.02 times of the weight of the truck when driving at a constant speed on a horizontal highway. How much traction is the engine on the truck when the truck is running?
The force analysis of the truck is as follows: from the question: g = mg = 8000kg × 10N / kg = 8 × 104nf = 0.02g = 0.02 × 8 × 104n = 1600NF traction = f = 1600n answer: when the truck is running, the traction of the engine on the truck is 1600n
The friction resistance of a truck with a mass of 8t is 0.02 times of the weight of the truck when driving at a constant speed on a horizontal highway. How much traction is the engine on the truck when the truck is running?
The force analysis of the truck is as follows: from the question: g = mg = 8000kg × 10N / kg = 8 × 104nf = 0.02g = 0.02 × 8 × 104n = 1600NF traction = f = 1600n answer: when the truck is running, the traction of the engine on the truck is 1600n
For a 2T agricultural vehicle, the rated power of the engine is 30kW, and the maximum speed of the vehicle is 54km / h when the vehicle is running on the horizontal road. If the vehicle accelerates from standstill with rated power, what is the instantaneous acceleration when the speed reaches v = 36km / h?
When the traction is equal to the resistance, the maximum speed is p = FV = FVF = PV = 3000015n = 2000N. When the speed is 36km / h, the traction is f ′ = PV ′ = 3000010n = 3000n. According to Newton's second law, f-f = MAA = f − FM = 3000 − 2000m / S2 = 0.5m/s2
The mass of the car is 2T, the engine power is 30kW, and it can run at the maximum speed of 54km / h on the horizontal road. If the power remains unchanged, the acceleration of the car is ()
A. 0.5 m/s2B. 1 m/s2C. 1.5m/s2D. 2 m/s2
When the traction and resistance are equal, the maximum speed of the car is VM = 54km / h = 15m / s, which can be obtained from P = FVM = FVM, resistance f = PVM = 3000015n = 2000N, when the speed reaches v = 36km / h = 10m / s, the traction of the car is f = PV = 3000n, which can be obtained from Newton's second law, f-f = ma, so a = f − FM = 3000 −
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