Question

A ball is dropped from a height time taken to reach ground is 4 sec find height

Answer 1

Answer:

height = 80 m

Step-by-step explanation:

given that,

A ball is dropped from a height

so,here

we have ,

initial velocity of the ball = 0 m/s [it was at rest]

also given that,

time taken to reach ground is 4 sec

so,

now we have,

initial velocity(u) = 0 m/s

time taken(t) = 4 seconds

gravitational acceleration(g) = -10 m/s²

let the height from which it dropped be h

so,

by the gravitational equation of motion,

h = ut + ½ gt²

putting the values,

h = 0(4) + ½ × (-10)(4)²

h = -80 m

negation of height shows the height in the downward direction

so,

Height = 80 m

Answer 2

Step-by-step explanation:

ANSWER:-

Height=80m

Initial velocity = 0 m/s(dropped from height)

Time Taken = 4 seconds

Gravitation (g) = -10 m/s²

USING IDENTITY:-

h=ut+½gt²

HENCE,

h=0×4+½×(-10)(4)²

h=-80

HEIGT IS NEGATIVE IT SHOWS THE HEIGHT IN THE DOWNWARD DIRECTION.

HENCE,

H=80m