PSc Day 7

A person places a metal spoon that is at room temperature into a bowl of hot soup. How

will the thermal energies of the spoon and the soup be affected?

• The spoon will increase in thermal energy, and the soup will decrease in thermal energy.

• Both the spoon and the soup will increase in thermal energy.

• The spoon will decrease in thermal energy and the soup will increase in thermal energy.

• Both the spoon and the soup will decrease in thermal energy.

Which is the lowest point of a

transverse wave?

• crest
• peak
• node
• trough

An object has a mass of 12.8 kg and

a velocity of 8.4 m s. What is the

kinetic energy of the object?

• 53.8 J

• 107.5 J

• 451.6 J

• 903.2 J

How much potential energy does a

55-kg person gains when she walks to

the top of a hill 20 m tall?

• 75 J

• 539 J

• 1100 J

• 10780 J

A student builds an electromagnet using a variable power source and 40 turns of wire.

The electromagnet is used to pick up metal paper clips. The student changes the voltage

and counts the number of paper clips that are picked up. Which table could be the data

the student collected?

• 
• 
• 
• 

Which statement best explains why there could be a force of attraction between

two electrically charged objects?

• because they have like charges

• because they have unlike charges

• because they have the same number of protons

• because they have the same number of electrons

A metal spoon is used to stir a pot of

boiling water. The person holding the

metal spoon feels the spoon get hot.

Which best describes the transfer of

heat in the spoon?

• Conduction
• Radiation
• Insulation
• Convection

25. A student moves a box across the floor

by exerting 23.3 N of force and doing

47.2 J of work on the box. How far

does the student move the box?

• 23.9 meters

• 1100 meters

• 2.02 meters
• 0.49 meters

A sound wave has a frequency of

247 Hz and a wavelength of 1.4 m.

What is the speed of the sound wave

in air?

• 176.4 m/s

• 245.6 m/s

• 248.4 m/s

• 345.8 m/s

What happens to the kinetic energy

and gravitational potential energy of

a ball during free fall?

• Gravitational potential energy

  and kinetic energy both increase.

• Gravitational potential energy

  and kinetic energy both decrease.

• Gravitational potential energy

  decreases, and kinetic energy

  increases.

• Gravitational potential energy

  increases, and kinetic energy

  decreases.