Understanding Motion and Forces

What is the difference between speed and velocity?

• Speed is scalar; velocity is vector (includes direction).

• Speed can be negative while velocity cannot.

• Velocity measures distance only, not direction.

• Speed is always greater than velocity.

How do you calculate average speed?

• Average Speed = Total Distance + Total Time

• Average Speed = Total Time / Total Distance

• Average Speed = Distance x Time

• Average Speed = Total Distance / Total Time

What is the formula for velocity?

• Velocity = Distance / Speed

• Velocity = Acceleration x Time

• Velocity = Displacement / Time

• Velocity = Time / Displacement

Define acceleration in your own words.

• Acceleration is the speed of an object at a given moment.

• Acceleration is the change in velocity per unit of time.

• Acceleration is the force applied to an object.

• Acceleration is the distance traveled over time.

What is the unit of acceleration?

• m/s²

• ft/s

• km/h

• m/s

How does Newton's first law of motion describe inertia?

• Inertia is the force that causes an object to move.

• Inertia only applies to objects in motion, not at rest.

• Inertia is the tendency of an object to accelerate when a force is applied.

• Inertia is the property of an object to maintain its state of rest or uniform motion unless acted upon by an external force.

What does Newton's second law of motion state?

• The force acting on an object is equal to its mass multiplied by its velocity.

• An object in motion will stay in motion unless acted upon by an equal force.

• The acceleration of an object is constant regardless of the net force applied.

• The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

Explain Newton's third law of motion with an example.

• When you throw a ball, it travels in a straight line without any force acting on it.

• When you push against a wall, the wall moves towards you.

• An example of this is when you jump off a small boat onto a dock. As you push down and back on the boat (action), the boat pushes you up and forward (reaction), causing it to move backward.

• A car accelerates forward without any push from the engine.

What factors affect friction between two surfaces?

• The temperature of the air

• The size of the objects involved

• The nature of the surfaces, materials, normal force, and presence of lubricants.

• The color of the surfaces

How does friction impact the motion of an object?

• Friction opposes motion and can slow down or stop an object.

• Friction increases the speed of an object.

• Friction has no effect on the motion of an object.

• Friction only acts on objects in water.