Answer:
2500 N
Explanation:
Draw a free body diagram of the bus. There are three forces:
Weight force mg pulling down,
Normal force N pushing perpendicular to the ramp,
and friction force F pushing parallel to the ramp.
Sum of forces in the parallel direction:
∑F = ma
F − mg sin θ = 0
F = mg sin θ
F = (5000 N) (sin 30°)
F = 2500 N