GENERAL SCIENCE SUMMATIVE TEST 1 REVIEWER

Practice flashcards covering motion basics, types of motion, simple and compound machines, levers, and efficiency concepts for a general science summative test.

What is the definition of motion?

Motion is the change in position from an initial position to a final position.

How is position defined?

Position is the location of an object.

What is the difference between distance and displacement?

Distance is the total path traveled with no direction, while displacement is the straight-line change in position with direction.

What is the definition and unit for speed?

Speed is distance divided by time and its unit is $m/s$.

How is velocity defined?

Velocity is displacement divided by time; it is speed with direction and the rate of change of displacement.

What is acceleration and what is its unit?

Acceleration is the change in velocity divided by time; it is the rate of change of velocity and its unit is $m/s^2$.

What is translational motion?

Translational motion occurs when the whole object or its center moves from one place to another, such as an elevator or a jeepney on a road.

What is rotational motion?

Rotational motion occurs when an object turns about an axis or fixed point, such as a fan blade or doorknob.

Define oscillatory or vibrational motion and provide examples.

Oscillatory or vibrational motion is repeated back-and-forth motion, such as a pendulum, spring, or guitar string.

What is combined or rolling motion?

Combined or rolling motion is translation and rotation together, such as a bicycle wheel rolling forward.

What is the core rule for how simple machines make work easier?

Simple machines make work easier by changing the size of force, the direction of force, or the distance over which the force acts.

What is the key idea of a lever?

A lever is a bar that turns around a fulcrum.

How does an inclined plane reduce effort?

An inclined plane is a slanted surface that reduces effort by increasing distance.

Definition of a pulley:

A pulley is a rope over a wheel that changes direction or reduces effort.

What is the key idea of a screw?

A screw is an inclined plane wrapped around a cylinder.

What are the three components of a lever system?

The fulcrum (fixed pivot), the effort (force applied by user), and the load (object being moved).

Where is the fulcrum located in a 1st class lever?

The fulcrum is between the effort and the load.

What defines a 2nd class lever?

In a 2nd class lever, the load is between the fulcrum and the effort.

What defines a 3rd class lever?

In a 3rd class lever, the effort is between the fulcrum and the load.

What is the formula for Mechanical Advantage (MA)?

$$MA = \text{load} \text{ / } \text{effort}$$

What is the definition of efficiency according to the reviewer?

$$\text{Efficiency} = \text{useful output} + \text{input} \times 100 \text{\%}$$

How does friction affect a machine?

Friction occurs when surfaces rub, causing heat, wear, slowing down, and energy loss.

What is the purpose of lubrication?

Lubrication using oil or grease reduces friction, wear, and energy loss.

Why are real machines not 100\% efficient?

Real machines are not 100\% efficient because friction always wastes some energy.

Which machines make up the compound machine of a pair of scissors?

Scissors consist of two levers and wedge-shaped blades.

What type of motion and machine is a doorknob?

A doorknob is a wheel and axle that performs rotational motion.

What simple machines compose a wheelbarrow?

A wheelbarrow is a combination of a 2nd class lever and a wheel and axle.

Why is a bicycle considered a compound machine?

A bicycle is a compound machine because it consists of a wheel and axle, levers, and gears/chain.