Question

A 2000-lb car drives from Denver (altitude: 5280 feet) to Los Angeles (sea level). What is its change in potential energy, in BTU? g = 32.174 ft/s² Provide your answer rounded to one decimal place, and make sure to include units. *

2) The velocity of an object increases by 50% (V₂=1.5 V₁). By what factor does the kinetic energy increase? *
1
4
1.5
2.25

Answer 1

Answer:

Explanation:

Loss of potential energy

= mgh

= 2000 x 5280 x 32.174

= 339757440 ft-poundal

1 BTU = 25036.86 ft-poundal

Loss of PE in BTU

= 339757440 / 25036.86

= 13570.3 BTU.

2 ) E = 1/2 m V²

When V increases to 1.5 V

E₁ = 1/2 m( 1.5V )²

= 2.25 X 1/2 m V²

= 2.25 X E.

Kinetic energy increases by a factor of 2.25.