Question

A cyclist is coasting at 4.5m/s when she starts down a 3.5 degree, 180m long straight slope. The cyclist and her bicycle have a combined mass of 85kg. As she coasts down the slope, a steady 12N drag force due to resistance acts on her in the first half of the trip down. The drag force increases to 14N during the second half of the trip. What is her speed at the bottom of the slope?

Answer 1

height of the path, h = 180Sin3.5⁰ = 10.9887 m

mass, m =85kg, velocity at the starting point, u = 4.5m/s

let v be the velocity at the bottom, then from the conservation of energy

g = 9.8m/s²