JEE Main 2026 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 4 April 2026, Shift 1, Physics Q28

Question 28 of 75 in this shift, Physics question 3 of 25, Section A.

The time taken by a block of mass

m

to slide down from the highest point to the lowest point on a rough inclined plane is

50\ \%

more compared to the time taken by the same block on identical inclined smooth plane. Both inclined planes are at

45^\circ

with the horizontal. The coefficient of kinetic friction between the rough inclined surface and block is ______.

(1) $3/4$
(2) $2/3$
(3) $5/9$ Official answer
(4) $4/9$

Official answer

Option 3

NTA final key.

Chapter: Laws of Motion
Topic: Friction
Idea tested: Motion Down a Rough Incline

Same idea in other shifts

Asked 4× in all

6 Apr 2026, Shift 2 · Q46A block takes $t$ time to slide down a plane inclined at $45^\circ$ to the horizontal. If the surface is made smooth (frictionless), the…MediumNumerical value
8 Apr 2024, Shift 2 · Q33A given object takes n times the time to slide down $45^\circ$ rough inclined plane as it takes the time to slide down an identical…MediumSingle correct
26 Feb 2021, Shift 2 · Q19An inclined plane making an angle of $30^\circ$ with the horizontal is placed in a uniform horizontal electric field $200\ \frac{N}{C}$ as…HardDiagram basedHas a figure

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.