BITSAT2017PhysicsMotion in One DimensionActual
An aeroplane is flying in a horizontal direction with a velocity u and at a height of 2000 m . When it is vertically below a point A on the ground a food packet is released from it. The packet strikes the ground at point B . If A B = 3 km and g = 10 m s - 2 , then the value of u is
Options
- A54   km   h - 1
- B540   km   h - 1
- C150   km   h - 1
- D300   km   h - 1
Correct answer
B. 540   km   h - 1
Step-by-step solution
Given R = 3   km = 3000   m Range, R = u 2 h g ⇒   u = R g 2 h or u = 3000 × 10 2 × 2000 = 3000 × 1 20 = 150   m   s - 1 = 150 × 18 5   km   h - 1 = 540   km   h - 1