Question

An object is projected horizontally with the velocity 7m/s from a height of 90m. the time needed to hit the floor is.
pls

Answer 1

Answer:

R = 40 m ; it was projected horizontally

So that horizontal velocity =

t

R

t = time ti free fall a height 20 m

↓

as initial vertical velocity = 0

Given by h=

2

1

9t

2

we have t =

9

2h

t=

10

2×20

= 2sec

& vertical velocity gained in these 2 sec

v

y

=u+9t=0+10×2=20 m/s

Horizontal velocity v

x

=

t

R

=

2

40

=20m/s (constant)

⇒ speed =

v

y

2

+v

x

2

=20

2

m/s

Answer 2

Explanation:

Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. The surrounding gas must not be saturated with the evaporating substance. When the molecules of the liquid collide, they transfer energy to each other based on how they collide with each other.