Astone is thrown straight up from the ground with an initial speed of 15.2 m/s. at the same instant, a stone is dropped from a height of h meters above ground level. the two stones strike the ground simultaneously. find the height h. the acceleration of gravity is 9.8 m/s 2 . answer in units of m.

47 m

Explanation:

Time of flight of stone thrown up = time of fall of stone dropped down.

Time of flight = 2u /g

where u is initial velocity and g is acceleration due to gravity.

= 2 x 15.2 / 9.8

=3.10 s.

For fall of second stone

time of fall t = 3.1 s

Height h = ?

h = ut + .5 g t²

= 0 + .5 x 9.8 x 3.1 x 3.1

= 47 m

found in the nucleus

has mass of one amu

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2