Look at the following set of measurements for the length of a test tube made by as student and determine ALL responses that are CORRECT. The actual value of its length is. 2.04 cm.
A. 2.039 cm
B. 2.040 cm
C. 2.041 cm
D. 3.097 cm

2.040 cm

Explanation:

If we study the options closely, we will discover that the chosen option is exactly the same as the actual value of the length of the test tube.

Hence it follows that the option chosen in the answer represents the actual measurement of the length of the test tube as stated above

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