Students in a science class learn that groundwater is an important source of drinking water for many communities. They construct a model
to study how leaking chemicals from a landfill can affect groundwater.
What is the most effective way for the students to see how leaking
chemicals from a landfill can enter a well?
Select one:

A: Pump water out of the well to see how stained water from the tissue paper
moves toward the well.

B: Drop food color into the well at the well's opening.

C: Tear some of the colored tissue paper and put the paper pieces into the well at
the well's opening

D: Tilt the tank towards the well and drain some of the water out of the tank.

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j

weight of any object is given by

w = m*g

where m is mass of the object and g is the acceleration due to gravity.

for earth the value of g is 9.8 m/s^2 so

w=117.6 n m=12 g=?

117.6=12g => g=9.8 m/s^2

which is the force of gravity on earth.