Question

A stone is thrown vertically upwards to break a
mango from the tree, at a height of 20 m from
the ground. If it takes 2 sec to reach the mango,
the initial speed of the stone, with which it was
thrown upwards is m/s. (take g = 10
m/s2)
20​

Answer 1

Use Newton’s 2nd law

force = mass * acceleration

F = ma

for gravity on Earth, ma = -mg

You can equate this to the initial velocity like this:

a = (final velocity - initial velocity) / time

At max height, the velocity is 0, so

a = (0 - 20) / time = -20 / time

so going back to Newton’s 2nd law

m * -20 / time = -mg

g is a constant on Earth, 9.8 m/s^2

Divide both sides by -m and rearrange for time

Time = 20 / 9.8 = about 2 seconds

hope it will help you..

Answer 2

Answer:

A stone is thrown vertically upwards to break a

Explanation:

A stone is thrown vertically upwards to break a

mango from the tree, at a height of 20 m from

the ground. If it takes 2 sec to reach the mango,

the initial speed of the stone, with which it was

thrown upwards is m/s. (take g = 10

m/s2)

20