Question

The mass of a bicyclist and bike is 80 kg. The drag coefficient is 0.79. Frontal area is 0.42 m^2. The density of air is 1.1 kg/m^3 at this elevation. The terminal velocity is reached when the drag force of a free falling object is equal to the weight.

a)Estimate the magnitude of the terminal velocity of the cyclist after he has ridden his bike off of a cliff. Assume that the frontal area remains constant during the fall.

b)Estimate the terminal velocity of the cyclist coasting down an incline of 15 degrees. Note that it is not the entire weight of the cyclist that is pulling him down the hill. Assume no friction in the wheels.

c) What happens to the terminal velocity of the cyclist as his mass is increased?

d) What is the magnitude of the drag force when the cycling velocity is equal to the terminal velocity in part b?

e) How much negative work would the drag force in part d do during a 40 km ride?

Answer #1

1. When a parachute opens, the air exerts a large drag force on
it. This upward force is initially greater than the weight of the
sky diver and, thus, slows him down. Suppose the weight of the sky
diver is 913 N and the drag force has a magnitude of 1079 N. The
mass of the sky diver is 93.2 kg. Take upward to be the positive
direction. What is his acceleration, including sign?
2. The space probe Deep Space...

1. For a stationary ball of mass m = 0.200 kg hanging from a
massless string, draw arrows (click on the “Shapes” tab) showing
the forces acting on the ball (lengths can be arbitrary, but get
the relative lengths of each force roughly correct). For this case
of zero acceleration, use Newton’s 2nd law to find the
magnitude of the tension force in the string, in units of Newtons.
Since we will be considering motion in the horizontal xy plane,...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 37 minutes ago

asked 51 minutes ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 3 hours ago

asked 3 hours ago

asked 3 hours ago

asked 3 hours ago

asked 4 hours ago

asked 4 hours ago

asked 4 hours ago