Question

A sled is moving down a steep hill. The mass of the sled is 50 kg and the net force acting on it is 20 N. What must be done to find the acceleration of the sled? Check all that apply.

The force of gravity must be broken into its parallel and perpendicular components.
Acceleration can be found by dividing the net force by mass.
Acceleration can be found by multiplying the net force by mass.
The magnitude of the force components must be multiplied by gravity.
Trigonometry can be used to solve for the magnitude of the force components.
Net force must be found before acceleration can be found.

Answer 1

Correct choices:
- Acceleration can be found by dividing the net force by mass.
- Net force must be found before acceleration can be found.

Explanation and result:
By Newton's 2nd law a = Fnet / m. Here a = 20 N / 50 kg = 0.40 m/s^2.

The other statements (resolving gravity into components, multiplying force components by gravity, or multiplying net force by mass) are not required here — resolving gravity/trigonometry is only needed if you must calculate the net force from gravity and friction, but the problem already gives Fnet = 20 N.