Question

33. An object of mass m at a height h with initial velocity zero, and reach the ground in 2sec. Find
the height of the building?​

Answer 1

Answer:

19.6 m approximately 20 m

Step-by-step explanation:

using this formulae, h= ut+1/2gtsquare

h=0(2)+1/2(9.8)2×2

h=9.8×2 = 19.6 m

Answer 2

Step-by-step explanation:

initial velocity(u) = 0

time = 2 seconds

acceleration = g = 9.8m/s²

using formula

v = u + at

v = 0 + 9.8 × 2

= 19.6m/s

Let the height be h,

now using the formula v² - u² = 2ah

(19.6)² - (0)² = 2 × 9.8 × h

=》(19.6)² = 19.6 × h

=》(19.6)²/19.6 = h

=》h = 19.6 m