Question

A projectile is fired horizontally from a height of
19.62 cm from the ground and reaches the ground
at a horizontal distance of 49 m. The initial velocity
is approximately plzz explain
​

Answer 1

you mean, A projectile is fired horizontally from a height of 19.62cm from the ground and reaches the ground at a horizontal distance of 49m.

it can be solved easily with help of equation of trajectory of projectile.

using equation of trajectory of projectile.

i.e., y = gx²/2u²

here , y is height of projectile, i.e., y = 19.62cm or 19.62 × 10^-2 m

x is horizontal distance , i.e., x = 49m

now

g = 9.8 m/s² [ acceleration due to gravity ]

19.62 × 10^-2 = 9.8(49)²/2u²

or, u² = 4.9 × (49)²/(19.62 × 10^-2)

or, u = 244.87507 m/s ≈ 245 m/s

hence, initial velocity of projectile will be 245 m/s.