Question 1

A student touches a metal sink with her finger and notices that her finger feels cold. Which of the following statements explains this observation?
A)Heat energy flows from the student's finger to the metal sink.
B)Heat energy flows from the metal sink to the student's finger.
C)The student's finger was originally at the same temperature as the sink.
D)The student's finger was originally at a lower temperature than the sink.

Accepted Answer

Heat energy flows from the student's finger to the metal sink because the metal, being a good conductor, quickly draws heat away from the warmer object in contact with it (in this case, the student's finger), making the finger feel cold.

Question 2

A student leaving school walks 2.5 km north and then walks 1.0 km south. What is the student's displacement?
A)1)0 km south
B)1)5 km north
C)2)5 km north
D)3)5 km south

Accepted Answer

Displacement is the shortest distance from the initial to the final position, direction included. Here, it's 2.5 km north - 1.0 km south = 1.5 km north.

Question 3

A student pushes a book across a classroom table. Which of the following statements best explains the difference between the amount of force needed to start the book moving and the amount of force needed to keep it moving?
A)Less force is needed to start the book moving, because there is less friction than when it is already moving.
B)Less force is needed to start the book moving, because there is less potential energy in the table than in the book.
C)More force is needed to start the book moving, because there is more potential energy in the table than in the book.
D)More force is needed to start the book moving, because there is more friction than when it is already moving.

Accepted Answer

Static friction, which must be overcome to start an object moving, is generally greater than kinetic friction, which is the frictional force encountered when an object is already in motion.

Question 4

In which of the following examples is heat transferred primarily by radiation?
A)A fan blows warm air around a room.
B)A hot water bottle warms a person's feet.
C)Water vapor from a shower warms the room.
D)A spoon held near the side of a flame gets warm.

Accepted Answer

Radiation is the transfer of heat through electromagnetic waves, which does not require a medium to travel through. In option D, the spoon gets warm due to the infrared radiation emitted by the flame, even though it is not directly in contact with it.

Question 5

Which of the following observations demonstrates that visible light waves are electromagnetic and not mechanical?
A)Sunlight can pass through gas.
B)Sunlight can pass through solids.
C)Sunlight can pass through liquids.
D)Sunlight can pass through a vacuum.

Accepted Answer

Electromagnetic waves, unlike mechanical waves, do not require a medium to travel through. The fact that sunlight (which is composed of visible light waves) can travel through a vacuum (space) demonstrates that these waves are electromagnetic in nature, as they can propagate without a medium.

Question 6

The momentum of an object in space is
A)dependent on its mass.
B)independent of its inertia.
C)independent of its velocity.
D)dependent on its potential energy.

Accepted Answer

Momentum is directly proportional to the mass of an object; the more mass an object has, the more momentum it can have at a given velocity.

Question 7

Which of the following is an example of heat transfer by conduction?
A)sunlight heating a floor
B)an electric stove heating an iron pan
C)a wood stove heating nearby objects through electromagnetic waves
D)an electric heater heating air, which rises and is replaced with cooler air

Accepted Answer

Conduction is the process of heat transfer through direct contact between materials, and an electric stove heating an iron pan is an example of this, as the heat is directly transferred from the stove to the pan through physical contact.

Question 8

The source of a sound is moving away from an observer who is standing still. How do the sound waves received by the observer compare with those emitted by the source?
A)They are heard as having a greater velocity.
B)They are heard as having a higher frequency.
C)They are heard as having a lower frequency.
D)They are heard as having a smaller wavelength.

Accepted Answer

When a sound source moves away from an observer, the sound waves stretch out, leading to a lower frequency being perceived by the observer. This phenomenon is known as the Doppler effect.

Question 9

Which of the following statements best describes the visible spectrum of light as seen by the human eye?
A)The lowest frequency appears red, and the highest frequency appears violet.
B)The lowest frequency appears red, and the highest frequency appears yellow.
C)The lowest frequency appears green, and the highest frequency appears violet.
D)The lowest frequency appears green, and the highest frequency appears yellow.

Accepted Answer

The visible spectrum of light, as perceived by the human eye, ranges from red at the lowest frequency to violet at the highest frequency. This spectrum is often represented in the color sequence of a rainbow.

Question 10

The speed of sound in a particular gas is 900 m/s. A sound wave propagating in this material has a wavelength of 15 m. What is the frequency of this sound?
A)30 Hz
B)60 Hz
C)6,800 Hz
D)13,500 Hz

Accepted Answer

The frequency of a sound wave is calculated using the formula $f = \frac{v}{\lambda}$, where $f$ is the frequency, $v$ is the speed of sound in the medium, and $\lambda$ is the wavelength. Substituting the given values, $f = \frac{900 \, \text{m/s}}{15 \, \text{m}} = 60 \, \text{Hz}$.

Question 11

Which of the following statements best describes an electromagnetic wave with a long wavelength?
A)It has a low frequency and can travel in a vacuum.
B)It has a high frequency and can travel in a vacuum.
C)It has a low frequency and can only travel in a medium.
D)It has a high frequency and can only travel in a medium.

Accepted Answer

Electromagnetic waves with long wavelengths have low frequencies, as wavelength and frequency are inversely related. Additionally, all electromagnetic waves, regardless of their wavelength or frequency, can travel in a vacuum.

Question 12

Based on Ohm's law, which of the following statements explains what must happen when the voltage across a resistor is decreased?
A)The resistance of the resistor increases.
B)The resistance of the resistor decreases.
C)The current through the resistor increases.
D)The current through the resistor decreases.

Accepted Answer

Ohm's law states that the current through a conductor between two points is directly proportional to the voltage across the two points. Therefore, if the voltage across a resistor is decreased, the current through the resistor also decreases, assuming the resistance remains constant.

Question 13

Which of the following waves travels fastest?
A)water waves in oceans
B)seismic waves in rocks
C)sound waves from a violin string
D)electromagnetic waves from the Sun

Accepted Answer

Electromagnetic waves, which include light waves from the Sun, travel at the speed of light in a vacuum, which is approximately 299,792 kilometers per second. This speed far exceeds that of water waves, seismic waves, or sound waves in their respective mediums.

Question 14

Which of the following can carry light waves but not sound waves?
A)air
B)steel
C)water
D)vacuum

Accepted Answer

Light waves can travel through a vacuum because they are electromagnetic waves, which do not require a medium to propagate. Sound waves, on the other hand, are mechanical waves that need a medium (like air, steel, or water) to travel through, and thus cannot propagate through a vacuum.

Question 15

A sailboat travels 35 km in 5 hr. Which of the following describes the motion of the sailboat?
A)Its momentum is 7 km/hr.
B)Its acceleration is 7 km/hr.
C)Its displacement is 7 km/hr.
D)Its average speed is 7 km/hr.

Accepted Answer

The sailboat's average speed is calculated by dividing the total distance traveled by the total time taken, which is 35 km / 5 hr = 7 km/hr.

Question 16

A pitcher throws a 0.15 kg baseball at 40 m/s towards the catcher. What is the momentum of the baseball while moving at 40 m/s?
A)0)025 kg • m/s
B)3)8 kg • m/s
C)6)0 kg • m/s
D)270 kg • m/s

Accepted Answer

The answer of A pitcher throws a 0.15 kg baseball...

Question 17

An astronaut drops a 1.0 kg object and a 5.0 kg object on the Moon. Both objects fall a total distance of 2.0 m vertically. Which of the following best describes the objects after they have fallen a distance of 1.0 m?
A)They have each lost kinetic energy.
B)They have each gained the same amount of potential energy.
C)They have each lost the same amount of potential energy.
D)They have each gained one-half of their maximum kinetic energy.

Accepted Answer

The answer of An astronaut drops a 1.0 kg object...

Question 18

Which of the following changes occurs as a solid is heated?
A)The kinetic energy of the solid decreases.
B)The average density of the solid increases.
C)The speci?c heat capacity of the solid decreases.
D)The average molecular speed in the solid increases.

Accepted Answer

As a solid is heated, the particles gain energy and vibrate more vigorously, which increases their average molecular speed. The kinetic energy of the particles increases with temperature, leading to this effect.

Quiz 3: Hesi: Introductory Physics

A student touches a metal sink with her finger and notices that her finger feels cold. Which of the following statements explains this observation?

A student leaving school walks 2.5 km north and then walks 1.0 km south. What is the student's displacement?

A student pushes a book across a classroom table. Which of the following statements best explains the difference between the amount of force needed to start the book moving and the amount of force needed to keep it moving?

In which of the following examples is heat transferred primarily by radiation?

Which of the following observations demonstrates that visible light waves are electromagnetic and not mechanical?

The momentum of an object in space is

Which of the following is an example of heat transfer by conduction?

The source of a sound is moving away from an observer who is standing still. How do the sound waves received by the observer compare with those emitted by the source?

Which of the following statements best describes the visible spectrum of light as seen by the human eye?

The speed of sound in a particular gas is 900 m/s. A sound wave propagating in this material has a wavelength of 15 m. What is the frequency of this sound?

Which of the following statements best describes an electromagnetic wave with a long wavelength?

Based on Ohm's law, which of the following statements explains what must happen when the voltage across a resistor is decreased?

Which of the following waves travels fastest?

Which of the following can carry light waves but not sound waves?

A sailboat travels 35 km in 5 hr. Which of the following describes the motion of the sailboat?

A pitcher throws a 0.15 kg baseball at 40 m/s towards the catcher. What is the momentum of the baseball while moving at 40 m/s?

An astronaut drops a 1.0 kg object and a 5.0 kg object on the Moon. Both objects fall a total distance of 2.0 m vertically. Which of the following best describes the objects after they have fallen a distance of 1.0 m?

Which of the following changes occurs as a solid is heated?