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In 1994, a tower 22.13 meter tall was built of Lego blocks. Suppose a block with a mass of 2.00 grams is dropped from the top of this tower. Neglecting air resistance, calculate the block's momentum at the instant the block hits the ground.

Respuesta :

Answer:

0.042 kg m/s

Explanation:

In order to solve this, we need to find the final velocity of the block at the moment it its the ground.

The motion of the block is a free fall motion, so it is a uniform accelerated motion, so we can use the following suvat equation:

[tex]v^2-u^2=2as[/tex]

where:

v is the final velocity

u = 0 is the initial velocity (it starts from rest)

[tex]a=g=9.8 m/s^2[/tex] is the acceleration of gravity (we chose downward as positive direction)

s = 22.13 m is the displacement

Solving for v,

[tex]v=\sqrt{u^2+2as}=\sqrt{0+2(9.8)(22.13)}=20.8 m/s[/tex]

Now we can find the final momentum of the block, using the equation:

p = mv

where

m = 2.0 g = 0.002 kg is the mass of the block

Substituting,

[tex]p=(0.002)(20.8)=0.042 kg m/s[/tex]