Forces, Motion, and Energy Study Guide

These flashcards cover key concepts, definitions, and calculations related to forces, motion, and energy.

What is friction?

The resistive force between an object and a surface.

What are the four types of friction?

1. Static - keeps an object at rest. 2. Sliding - surfaces slide past each other. 3. Rolling - object rolls. 4. Fluid - movement through liquid or gas.

What type of friction keeps an object at rest?

Static friction.

What is a force?

A push or a pull.

What is the unit for force?

Newtons.

What is net force?

The overall force acting on an object after all forces are combined, including direction.

Calculate the net force: A 20 N force pushes right and a 5 N force pushes left. What is the net force?

15 N to the right.

How do you calculate the net force when three forces act: 10 N right, 7 N right, and 12 N left?

The net force is 5 N to the right.

What is Newton's 1st law?

An object at rest stays at rest, and an object in motion stays in motion unless acted on by an unbalanced force.

What is Newton's 2nd law formula?

F=ma.

What is the mass unit in the SI system?

Kilograms (kg).

What is the acceleration in units?

Meters per second squared (m/s²).

What force is produced by a 1,500 kg rocket accelerating at 8 m/s²?

12,000 N.

What is Newton's 3rd law?

For every action, there is an equal and opposite reaction.

Give an example of Newton's 3rd law.

When you jump, you push down on the ground, and the ground pushes you up.

What is the kinetic energy of a 4 kg object moving at 3 m/s?

18 J.

Calculate the kinetic energy of a 10 kg object moving at 5 m/s.

125 J.

What is the potential energy of a 5 kg object lifted 10 m?

490 J.

Calculate the potential energy of an object with a mass of 50 kg lifted 12 m.

5880 J.

What is the formula for kinetic energy?

KE = rac{1}{2}mv².

Calculate the mass of an object with a kinetic energy of 800 J, moving at 8 m/s.

25 kg.