Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NTA Abhyas 2020
Exam
NTA Abhyas
Year
2020
Subject
Physics
Chapter
Motion in Two Dimensions

NTA Abhyas 2020 · Physics · Motion in Two Dimensions

A particle A is projected from the ground with an initial velocity...

A particle AA is projected from the ground with an initial velocity of 10ms−110ms^{- 1} at an angle 60°60 ° with horizontal. From what height (in m\text{m}) directly above the point of projection of the particle AA, should another particle BB be projected horizontally with velocity 5ms−15ms^{- 1} so that both the particles collide right before they strike the ground?~[g=10ms−2g = 10ms^{- 2}]

Correct answer

15

Step-by-step solution

Both the particles will meet at CC, if their time of flight is the same. The time of flight of AAis

T=2usinθg=2×10×sin⁡60∘10=3sT = \dfrac{2usin\theta}{g} = \dfrac{2 \times 10 \times \sin 6 {0}^{∘}}{10} = \sqrt{3}s

For vertical downward motion of particle BB from BB to CC

We have

h=12gT2=12×10×(3)2=15mh = \dfrac{1}{2}g{T}^{2} = \dfrac{1}{2} \times 10 \times {\left(\sqrt{3}\right)}^{2} = 15m
Practice Motion in Two Dimensions on Quantrex Academy →

More from Motion in Two Dimensions

A particle is thrown with a speed v from a point O at an angle θ with the horizontal… JEE Advanced 2026A car moving with a speed of 54 km/h takes a turn of radius 20 m. A simple pendulum is… JEE Main 2026Two identical bodies, projected with the same speed at two different angles cover the… JEE Main 2026If x and y coordinates of a projectile as a function of time (t) are given as 24t and… JEE Main 2026A gun mounted on the ground fires bullets in all directions with same speed. The farthest… JEE Main 2026Two projectiles are projected with the same initial velocities at the 15^∘ and 30^∘ with… JEE Main 2026A boy throws a ball into air at 45^ ∘ from the horizontal to land it on a roof of a… JEE Main 2026An object is projected with kinetic energy K from a point A at an angle 60^ ∘ with the… JEE Main 2026 Full Motion in Two Dimensions list All NTA Abhyas JEE Main PYQs