Energy and Motion
Which of the following actions demonstrates energy causing a change in motion?
A) Holding a soccer ball in both hands
B) Leaving a soccer ball resting on a shelf
C) Kicking a soccer ball across a field
D) Watching a stationary soccer ball on the grass
C) Kicking a soccer ball across a field
Two hanging balloons swing away from each other without touching. Why does this happen?
A) The balloons have the same static charge and repel each other.
B) The balloons have opposite charges and attract each other.
C) Neither balloon carries a static charge.
D) Air currents force them together.
A) The balloons have the same static charge and repel each other.
What is required for electrical current to continuously flow and light up a bulb?
A) An open switch connected with insulating materials
B) A complete, closed loop made of conducting materials
C) A plastic string connected to a battery
D) Removing the energy source from the loop
B) A complete, closed loop made of conducting materials
A student observes a leaf being carried downstream by a river and another leaf floating without moving in a puddle. What conclusion about energy and motion can be made?
A) Still water has more energy than moving water.
B) Water in motion has the energy to move objects.
C) Water never has enough energy to move solid objects.
D) All water sources exert the exact same amount of motion energy.
B) Water in motion has the energy to move objects.
After brushing hair with a plastic comb, the negatively charged comb is brought near positively charged tissue paper. What happens?
A) The paper is repelled by the comb.
B) The paper is attracted to the comb as it gets close.
C) Nothing happens until physical contact is made.
D) The paper loses all electrical charge instantly.
B) The paper is attracted to the comb as it gets close.
Which group of items consists entirely of good conductors of electrical energy?
A) Brass key, gold ring, metal paper clip
B) Glass rod, cork stopper, rubber eraser
C) Plastic button, aluminum foil, rubber ball
D) Cardboard, copper wire, glass rod
A) Brass key, gold ring, metal paper clip
When an air conditioner turns on, papers spread across a table fly off onto the floor. Which statement best evaluates this event?
A) The moving air transferred its energy of motion to the papers.
B) Moving air exerts force but contains no actual energy.
C) Papers are too heavy to absorb energy from moving air.
D) Moving air cools the papers down so they lose weight and float.
A) The moving air transferred its energy of motion to the papers.
Can electrically charged objects interact with other objects without making physical contact?
A) No, contact must occur before any push or pull happens.
B) Yes, charged objects can attract or repel without touching.
C) Only if both objects are made of metal.
D) Only if the objects are submerged in water.
B) Yes, charged objects can attract or repel without touching.
What intermediate form of energy does a speaker use to vibrate its cone and create sound energy?
A) Heat energy
b) Light energy
C) Chemical energy
D) Mechanical energy (motion)
D) Mechanical energy (motion)
Four identical blocks of wax are placed on separate heating pads. Which pad will melt the wax the fastest?
A) The pad set to 30 degrees Celsius
B) The pad set to 40 degrees Celsius
C) The pad set to 50 degrees Celsius
D) The pad set to 60 degrees Celsius
D) The pad set to 60 degrees Celsius
What reaction occurs when two objects with opposite static charges (positive and negative) are brought near each other?
A) They repel one another.
B) They attract one another.
C) They cancel out each other's mass.
D) They produce a continuous electric current.
B) They attract one another.
Into which energy transformation category do appliances like electric kettles, space heaters, and toasters belong?
A) Electrical energy to Sound energy
B) Electrical energy to Mechanical energy
C) Electrical energy to Heat energy
D) Electrical energy to Light energy
C) Electrical energy to Heat energy
When a player kicks a stationary football, what happens to the ball's mechanical energy?
A) Mechanical energy decreases, keeping the ball in place.
B) Mechanical energy increases, causing the ball to move across the field.
C) Mechanical energy drops to zero.
D) Mechanical energy transforms directly into visible light.
B) Mechanical energy increases, causing the ball to move across the field.
A charged rod pushes object X away but pulls object Y closer. What can be concluded about the charges of X and Y?
A) Object X has the same charge as the rod; Object Y has the opposite charge.
B) Object X has an opposite charge; Object Y has the same charge.
C) Both objects share the exact same charge as the rod.
D) Neither object carries an electric charge.
A) Object X has the same charge as the rod; Object Y has the opposite charge.
In a simple circuit, replacing a metal wire with a plastic string causes the light bulb to turn off. Why?
A) Plastic conducts electricity too quickly for the bulb.
B) Plastic is an insulator that breaks the path needed for current to flow.
C) Plastic drains all power from the battery.
D) The light bulb requires two batteries when plastic is used.
B) Plastic is an insulator that breaks the path needed for current to flow.