Final answer:
The force required to pull a 20 kg sled across a flat surface at constant velocity when the coefficient of friction is 0.03 is 5.88 N, which is the force that balances the frictional force.
Step-by-step explanation:
To find the force required to pull a sled with a constant velocity across a flat surface, we first need to determine the frictional force acting on the sled. The frictional force can be calculated using the equation Ffriction = μ * m * g, where μ is the coefficient of friction, m is the mass of the sled, and g is the acceleration due to gravity (approximately 9.8 m/s2). Given that the mass of the sled is 20 kg and the coefficient of friction is 0.03, the frictional force equals 0.03 * 20 kg * 9.8 m/s2, which calculates to 5.88 N.
To maintain a constant velocity, the applied force must equal the frictional force, thus, a force of 5.88 N is required.