Home › UAE MoE Grade 12 › Physics › Friction, Drag and Elasticity › Why does the speed stop changing once the net fo…
Why does the speed stop changing once the net force on a falling body is zero?
ABecause gravity switches itself off
BBecause no acceleration is produced
CBecause the mass becomes zero
DBecause drag reverses direction
Answer & Solution
Correct answer: B. Because no acceleration is produced
1. Newton's second law ties acceleration directly to the net force on a body.
2. With a zero net force there is no acceleration.
3. No acceleration means the velocity cannot change from that moment on.
4. So the body carries on at a steady speed, which is the terminal velocity.
_Source: OpenStax College Physics (CC BY 4.0), Ch 5 "Further Applications of Newton's Laws: Friction, Drag, and Elasticity", section 5.2 Drag Forces_
Related questions
The tip of a probe dragged across a material is deformed by atomic-scale friction. The forWhat happens to the downward force of gravity on a skydiver as their speed rises?Which two forces act on a skydiver falling through air, once buoyancy is ignored?What would a nearly friction-free environment save on a large scale?What kind of characteristics of friction are the simple rules taught at school?Which of these is the standard everyday example of kinetic friction acting?Why do two surfaces become warm when they are rubbed together?Adding a heavy box on top of a crate makes it harder to push. Why?