Coin

During a demonstration of Newton’s laws of motion, a student used the setup shown in Figure 1. The student flicked the index card with a fingertip, and the coin fell straight down into a plastic cup as shown in Figure 2. Which of these best explains why the coin fell straight down into the cup instead of remaining on the index card?

• The coin was at rest until the card was removed, so it tended to remain in the same location. Once the card was gone, the unbalanced force of gravity caused the coin to fall.

• Moving the card applied an action force on the coin. Since the card was gone, gravity applied a reaction force on the coin.

• The card had less mass than the coin, so a smaller force of gravity acted on the card. The larger force of gravity on the coin made it fall.

• The acceleration of the coin falling into the cup was equal and opposite to the acceleration of the card.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-4

Two coins are falling down a well. The kinetic energy of each coin depends on the coin's mass and speed.

Which coin has a greater speed?

• Nickel

• Penny

• They have the same speed

Tags

NGSS.MS-PS3-1

What is the primary metal used in the production of coins?

• Gold

• Silver

• Copper

• Aluminum

Which scientific principle explains why a coin sinks in water?

• Buoyancy

• Gravity

• Surface tension

• Magnetism

What is the process called when a coin changes color due to chemical reactions with the environment?

• Oxidation

• Reduction

• Sublimation

• Evaporation

Tags

NGSS.MS-PS1-2

Which of the following elements is most commonly used for coin plating?

• Nickel

• Zinc

• Lead

• Tin

What is the term for the study of coins and currency?

• Numismatics

• Cryptography

• Philately

• Cartography

Which property of metals makes them suitable for coin production?

• Malleability

• Brittleness

• Transparency

• Elasticity

What is the scientific term for the wear and tear of coins over time?

• Abrasion

• Corrosion

• Erosion

• Deposition

Which experiment can demonstrate the density of a coin?

• Water displacement method

• Pendulum experiment

• Electrolysis

• Spectroscopy