Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
COMEDK2023Morning ShiftPhysicsMotion in One DimensionActual

A body is projected vertically upwards. The times corresponding to height h while ascending and while descending are t₁ and t₂ , respectively. Then, the velocity of projection will be (take, g as acceleration due to gravity)

Options

  1. Ag t₁ t₂ (t₁+t₂ )
  2. Bg t₁ t₂ 2
  3. Cg t₁ t₂
  4. Dg (t₁+t₂ ) 2

Correct answer

D. g (t₁+t₂ ) 2

Step-by-step solution

Let u be the velocity of projection. The equation of motion for a body at height h is given by h = ut - 1 2 gt^2 . Rearranging the terms, we get a quadratic equation in t : 1 2 gt^2 - ut + h = 0 . The roots of this equation are t₁ and t₂ , which correspond to the times at which the body is at height h during ascent and descent, respectively. From the properties of quadratic equations, the sum of the roots is t₁ + t₂ = u g/2 = 2u g . The product of the roots is t₁ t₂ = h g/2 = 2h g . The total time of flight T is th

Practice Motion in One Dimension on Quantrex Academy →

More from Motion in One Dimension

An object is dropped from a certain point A at a height 'h' from the ground. During it's journey straight downwards, the object passes points B and C such that the ratio of time ta 2026A particle moves along a parabolic path y = 9x^2 in such a way that the x component of velocity remains constant. If, the acceleration of the particle is 2j ms⁻² , find the x compo 2026A car, starting from rest, accelerates at a rate of through a distance S, then continues at constant speed for time t and then decelerates at a rate of 2 to come to rest. If the to 2026A car covers the first half of the distance between two places at 40 km/h and another half at 50 km/h. The average speed of the car is 2026The velocity of a particle moving along x -axis is given as V = x^2 - 5x + 4 (in m/s) where x denotes the x -coordinate of the particle in metres. The magnitude of the acceleration 2026If the displacement (s in metre) of a moving particle in terms of time (t in second) is s=t^3-6 t^2+18 t+9 , then the minimum velocity attained by the particle is 2025A ball projected vertically upwards with a velocity 'v' passes through a point P in its upward journey in a time of ' x ' seconds. From there, the time in which the ball again pass 2025The displacement (x) and time (t) graph of a particle moving along a straight line is shown in the figure. The average velocity of the particle in the time of 10 s is 2025 Full Motion in One Dimension list All COMEDK PYQs