Home › CBSE Class 11 (Science) › Physics › Work, Energy and Power › A ball is dropped from 20 m (g = 10). Speed on h…
A ball is dropped from 20 m (g = 10). Speed on hitting ground?
A40 m/s
B20 m/s
C10 m/s
D14 m/s
Answer & Solution
Correct answer: B. 20 m/s
mgh = mv^2/2 gives v = sqrt(2 x 10 x 20) = 20 m/s.
Related questions
Horse-power is still commonly used to describe the output of:The potential energy of a body under a conservative force is always fixed only up to:Power, like work and energy, is what kind of physical quantity?The work-energy theorem holds in which frames of reference?Total mechanical energy of a body stays constant provided the only forces acting on it areAfter which inventor is the SI unit of power named?A motor pulls with a force of 22000 N at a steady 2 m/s. What power does it supply?During an elastic collision, the kinetic energy of the system at each instant of contact i