Will the Bulb Light? is a free printable Grade 4 science worksheet on evidence that an electric current carries energy only around a complete loop, aligned to NGSS performance expectation 4-PS3-2. It prints 7 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two students in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.
Set 3 of 25 · the same problems every time you open this link.
Set 1 has all 25 in a single PDF. All 25 sets ask different questions.
Will the Bulb Light?
4-PS3-2
NameDate
Read the record, then answer the questions.
1.Read the record, then answer the questions.
Will the Bulb Light?
Results from one battery, one bulb and some wires, set up eight different ways.
ONE BATTERY, ONE BULB, EIGHT SET-UPS
All the wires joined in a loop ............ bulb lit
One wire left loose ....................... bulb off
A foil strip across the gap ............... bulb lit
A wooden lolly stick across the gap ....... bulb off
A steel paperclip across the gap .......... bulb lit
A plastic ruler across the gap ............ bulb off
A buzzer added into the loop .............. bulb lit dimly, buzzer sounded
Bulb taken out, buzzer still in the loop .. buzzer silent
After a minute, the lit bulb felt warm.
Same battery, same bulb, same wires every time.
1. Why did the bulb light with the foil strip but not the lolly stick?
2. What happened when the foil strip was put across the gap?
3. Why did the buzzer go silent when the bulb was taken out?
4. What happened with the plastic ruler across the gap?
2.Why is the metal in a wire covered in plastic?
A.Plastic does not let the current through, so it is safe to hold
B.To make it brighter
C.To make it carry more energy
3.What does a switch do in a circuit?
A.It makes the battery stronger
B.It stores the energy
C.It opens or closes a gap in the loop
4.A bulb lights at the far end of a long wire. What does that show?
A.The wire made its own light
B.The bulb stored the energy beforehand
C.Energy traveled along the wire from the battery
5.Which shows electric current turning into sound?
A.A bulb glowing
B.A heater warming a room
C.A buzzer sounding when the switch closes
6.A buzzer and a bulb are in the same loop. The wire breaks. What happens?
A.Both get louder and brighter
B.Only the buzzer stops
C.Both stop, because the loop is no longer complete
7.A battery, a switch and a small motor are joined in a loop. What happens when the switch closes?
A.Nothing, motors need no energy
B.The battery turns instead
C.The motor turns, using energy carried from the battery
LessonPrint · 4-PS3-2 · Set 3 · free to copy for classroom use
Answer key — Will the Bulb Light?
Set 3. Prints on its own sheet.
1.1. The foil carried the current across the gap and completed the loop; the wooden lolly stick did not. 2. The bulb lit. 3. Taking the bulb out broke the loop, so nothing could reach the buzzer. 4. The bulb stayed off.
2.Plastic does not let the current through, so it is safe to hold
3.It opens or closes a gap in the loop
4.Energy traveled along the wire from the battery
5.A buzzer sounding when the switch closes
6.Both stop, because the loop is no longer complete
7.The motor turns, using energy carried from the battery
Last reviewed 2026-09-05. Aligned to 4-PS3-2 of the Next Generation Science Standards.