The Central Board of Secondary Education (CBSE) will hold the CBSE Class 10 examinations in 2026 from February 17 to March 10 . The CBSE Class 10 Science exam is scheduled for February 25, 2026 . Students preparing for this exam can use these important one-mark Physics questions to help with their studies.
The Class 10 Science examination consists of an 80-mark theory paper and a 20-mark internal assessment. For the 80-mark theory paper, Physics and Chemistry each carry 25 marks . Biology accounts for 30 marks .
CBSE Class 10 Science 2026: Marks Distribution
| Subject | Marks in Theory Paper |
| Physics | 25 |
| Chemistry | 25 |
| Biology | 30 |
| Total Theory Marks | 80 |
Important One-Mark Physics Questions for CBSE Class 10 (2026)
Question 1:
A concave mirror of radius 30 cm is placed in water. Its focal length in air and water differ by____
Answer: Zero
Question 2:
As light travels from a rarer to a denser medium it will have
Answer: decreased velocity and decreased wavelength
Question 3:
The nature of image formed by a convex mirror when the object distance from the mirror is less than the distance between pole and focal point (F) of the mirror would be:
Answer: virtual, upright and diminished in size
Question 4:
You are given three media A, B and C of refractive index 1.33, 1.65 and 1.46. The medium in which the light will travel fastest is
Answer: A
Question 5:
When object moves closer to convex lens, the image formed by it shift
Answer: first away and then towards the lens
Question 6:
When is the force experienced by a current-carrying conductor placed in a magnetic field largest?
Answer: at 90 degree
Question 7:
On which of the following does not exert any force when kept in uniform magnetic field?
Answer: Stationary Charge
Question 8:
For making a strong electromagnet, the material of the core should be
Answer: soft iron
Question 9:
The direction of magnetic field around a straight conductor carrying current can be determined by
Answer: right hand thumb rule
Question 10:
Magnetic field is produced by the flow of current in a straight wire. This phenomenon was discovered by
Answer: Oersted
Question 11:
If an electron is travelling horizontally towards east. A magnetic field in vertically downward direction exerts a force on the electron along
Answer: towards the South
Question 12:
Why is the absolute refractive index of a medium always greater than 1?
Answer: Because the speed of light in any medium is always less than its speed in a vacuum.
Question 13:
Magnetic lines of force inside current carrying solenoid are
Answer: along the axis and are parallel to each other.
Question 14:
If the power of a lens is (-2.0) D, what is its focal length and nature?
Answer: f=-50 cm; Concave lens
Question 15:
Why is a fuse wire made of a material with a low melting point?
Answer: To melt and break the circuit during current overflow
Question 16:
What is the frequency of AC supply in India?
Answer: 50 Hz
Question 17:
Does the resistivity of a wire change if its length is doubled?
Answer: No, it only depends on the material and temperature.
Question 18:
Why do two magnetic field lines never intersect?
Answer: Because at the point of intersection, the compass would point in two directions, which is impossible
Question 19:
What does the thumb represent in the Right-Hand Thumb Rule?
Answer: Direction of Current
Question 20:
How many Joules are there in 1 kWh?
Answer: 3.6×10 to the power of 6 J
Students should practice NCERT Exemplar Problems carefully. Many one-mark multiple-choice questions come directly from these problems. Focused practice will help in scoring well in the exam.
