physicshelpline - Question of the day , Kinematics

Projectile Motion

Fri, 05 Jun 2026 13:02:00 +0530

Q- A particle is projected in a vertical plane from a point O with velocity u at angle α to the horizontal. Find the time at which the particle is moving at angle θ to the horizontal.

Solution:

Maximum range down an incline

Sun, 22 Mar 2026 07:03:00 +0530

Q- Find the angle of projection φ with the incline to maximize the range of a projectile down the incline making an angle θ bellow horizontal and calculate this maximum range if the speed of projection is V0.

Solution:

Bug on sliding stick

Sat, 07 Feb 2026 09:22:57 +0530

Q- A stick of length L is placed vertically by the wall. At its lower end sits a bug. The end B of the stick starts moving to the right with constant speed v, and at the same moment the bug starts crawling along the stick with speed u relative to the stick. What is the maximal height above the floor that the bug reaches while it crawls along the stick? End A of the stick does not lose contact with the wall. Solution:

Particles on Triangles

Wed, 17 Dec 2025 08:36:09 +0530

Q- Three particles, located initially on the vertices of an equilateral triangle of side L, start moving with a constant tangential acceleration ’a’ towards each other in a cyclic manner, forming spiral loci that coverage at the centroid of the triangle. Find the length of one such spiral.

Solution:

Kinematics: Variable acceleration

Wed, 08 Oct 2025 23:19:00 +0530

Q- At t = 0, car A starts from rest at point 1. It moves with an acceleration of 0.4 t m/s^2. At the same time, car B starts from point 2, which is 225 m ahead, with a constant acceleration of 2 m/s^2 in the same direction. Find:

(a) Speed of car A at the end of the 225 m section.

(b) Time to travel 225 meters by car A.

(d) How far has car B moved when car A reached point 2?

Solution: