A car with a mass of m = 1.8 tons moves uphill, the slope of which is 3 m for every 100 m.

A car with a mass of m = 1.8 tons moves uphill, the slope of which is 3 m for every 100 m. Determine: 1) the work done by the engine of the car on the path of 5 km, if the coefficient of friction is 0.1; 2) the power developed by the engine, if it is known that this path was covered in 5 minutes.

m = 1.8 t = 1800 kg.

g = 9.8 m / s2.

S = 5 km = 5000 m.

μ = 0.1.

t = 5 min = 300 s.

L = 100 m.

h = 3 m.

A -?

N -?

We express the work of force A by the formula: A = F * S.

F = m * g * sinα + Ftr.

Ftr = μ * N.

N = m * g * cosα.

F = m * g * sinα + μ * m * g * cosα = m * g * (sinα + μ * cosα).

sinα = h / L.

sinα = 3 m / 100 m = 0.03.

∠α = 1.7 °.

cosα = 0.99.

F = 1800 kg * 9.8 m / s2 * (0.03 + 0.1 * 0.99) = 2276 N.

A = 2276 N * 5000 m = 11380000 J.

Power is determined by the formula: N = A / t.

N = 11,380,000 J / 300 s = 37933 W.

Answer: A = 11,380,000 J, N = 37933 W.