Newton’s 2nd Law & Air Resistance: Concepts and Calculations (Questions) For Exam #1

Is acceleration proportional to net force?

Yes, acceleration is proportional to net force; a greater net force results in more acceleration.

How does mass affect acceleration?

Mass affects acceleration inversely.

What happens to friction when you push a crate that doesn't move?

Friction is equal to your push.

Does friction increase as you increase your push on the crate?

Yes, friction increases to match your push until it reaches its maximum.

Why doesn't a heavy object accelerate more than a light object when freely falling?

Both fall with the same acceleration due to gravity; heavier objects have more gravitational force but also more mass.

What two factors affect the force of air resistance on a falling object?

Speed and surface area.

Which object encounters greater air drag when falling at different speeds?

The faster object encounters greater air drag.

Calculate the acceleration of a bike that goes from 8 m/s to 20 m/s in 4 s.

The acceleration is 3 m/s².

Rank the net forces on boxes A, B, C, and D from greatest to least.

D, A = B = C.

Rank the accelerations of boxes A, B, C, and D from greatest to least.

A = C to B = D.

How do you compute the net force for skydivers?

Net force = weight - air drag.

What is the net force on a Mercedes convertible traveling at a steady speed?

The net force is 0 N.

Does the mass of a junked car change when crushed into a cube?

No, the mass remains the same.

What is the acceleration of a ball at the top of its trajectory when thrown upward?

The acceleration is equal to g (gravity) downward.

Which basketball accelerates more when dropped, hollow or filled with rocks?

The rock-filled ball accelerates slightly more.

How does terminal speed change for a parachutist before and after opening the parachute?

Terminal speed is higher before opening and lower after due to increased surface area.

How does gravitational force compare with air drag before reaching terminal velocity?

Before terminal velocity, gravitational force is greater than air drag.

What happens to gravitational force and air drag at terminal velocity?

At terminal velocity, gravity equals air drag.