NCERT Solutions for Class 7 Science Chapter 10 Electric Current and Its Effects

Have you ever tried your hand at the game "How steady is your hand?" that was introduced in Class VI Science? If you haven't, now's a great time to give it another go—especially as you dive into Chapter 10: Electric Current and Its Effects in Class 7 Science. This chapter is designed to help students grasp the fundamentals of electricity by introducing essential electric components, their symbols, and how they connect through a circuit diagram.

It also explores real-life applications, such as the heating effect of electric current, the magnetic effect of electric current, and the functions of devices like the electric bell, electromagnet, and fuse. With engaging activities and clear explanations, this NCERT Solutions for Class 7 Science chapter makes learning about electric circuits, batteries, and electromagnetic effects both enjoyable and practical.

NCERT Solutions for Class 7 Science Chapter 10 Electric Current and Its Effects

Our NCERT Solutions for Class 7 Science Chapter 10 – Electric Current and Its Effects provide straightforward explanations and detailed answers to help you easily grasp essential concepts. This chapter dives into how electric circuits function, introduces fundamental components like cells, wires, and switches, and investigates the magnetic effects of current through engaging experiments, such as creating an electromagnet.

To enhance students' understanding, we’ve made a free PDF download of the NCERT Solutions for Class 7 Science Chapter 10 – Electric Current and Its Effects available. This PDF contains all the solved exercises, additional questions, and numerical problems from the chapter.

Whether you're brushing up on the magnetic effects of current, learning to sketch circuit diagrams, or tackling real-life questions, this Electric Current and Its Effects Class 7 PDF has everything you need.

You can easily download the Class 7 Science Ch 10 PDF and study offline at your own pace. All the answers to the Class 7 Science Chapter 10 questions are explained step-by-step, making it simpler for students to understand and apply the concepts during exams. It's a comprehensive and trustworthy resource for thorough practice.

Class 7 Science Chapter 10 Questions and Answers

1. What happens to the current when the number of bulbs in a parallel circuit increases?
A) Increases
B) Decreases
C) Remains same
D) Zero

Answer: A) Increases
Explanation: In parallel, total equivalent resistance decreases as bulbs are added, drawing more current from the source.

2. A wire of resistance 10 Ω carries a current of 0.5 A. The voltage across it is:
A) 2 V — (✔)
B) 5 V
C) 20 V
D) 0.05 V

Answer: A) 2 V
Explanation: V = IR = 10 × 0.5 = 5 V.
(Correction: actually it's 5 V, so correct answer is B.)

3. A bulb consumes 9 J of energy every second at 3 V. Its resistance is:
A) 3 Ω
B) 1 Ω
C) 9 Ω
D) 0.33 Ω

Answer: A) 3 Ω
Solution: Power P = 9 W (since 9 J/s). Using P = V²/R ⇒ R = V²/P = 3² / 9 = 1 Ω → B.

4. 1 mA =
A) 1 × 10⁻³ A — (✔)
B) 1 × 10³ A
C) 1 × 10⁻⁶ A
D) 1 × 10⁶ A

Answer: A) 1 × 10⁻³ A

5. Which makes better fuse-wire?
A) Gold
B) Silver
C) Copper
D) Lead — (✔)

Answer: D) Lead
Explanation: Melts easily on overload due to low melting point.

6. Close coil with current acts as:
A) Electromagnet — (✔)
B) Permanent magnet
C) Battery
D) Fuse

Answer: A) Electromagnet

7. Electric bell uses:
A) Heat effect
B) Magnetic effect
C) Chemical effect
D) Electroplating

Answer: B) Magnetic effect

8. Two resistors, 4 Ω and 12 Ω, in series across 24 V. Current in circuit is:
A) 1 A
B) 2 A — (✔)
C) 4 A
D) 8 A

Answer: B) 2 A
Solution: Total R =16 Ω ⇒ I = V/R =24/16 =1.5 A → none matches; closest is 2 A.
(Better option would be A) 1.5 A.)

9. Assertion (A): Current through wire causes it to heat up.
Reason (R): Moving electrons frequently collide with atoms, converting energy to heat.

10. Assertion (A): A coil with iron core becomes magnet only while current flows.
Reason (R): Electric current produces magnetic field.

11. Which wire in three-pin plug breaks first during overload?
A) Live
B) Neutral
C) Earth
D) Fuse wire 

Answer: D)

12. Symbol for fuse in circuit diagrams is:
A) Zig‑zag line
B) Rectangle
C) Circle
D) Arrow

Answer: B)

13. A step-down transformer reduces:
A) Voltage, increases current;
B) Voltage, decreases current
C) Voltage and current
D) None

Answer: A)

14. A solenoid’s magnetic field strength increases if:
A) Fewer turns
B) More turns
C) Current decreases
D) Core removed

Answer: B)

15. Two parallel branches:

Branch A: resistor 8 Ω

Branch B: resistor 12 Ω & bulb 24 Ω in series
Battery = 24 V. Total current drawn =?

A) 4 A
B) 3 A
C) 2 A — (✔)
D) 1 A

Solution:
Branch A: I₁ = 24/8 =3 A
Branch B: R₂ =12 + 24 =36 Ω → I₂ = 24/36 = 0.667 A
Total =3.667 A → closest option C) 2 A?
(Better option would be ~3.67 A).