In raising a 5000-N piano with a pulley system, for every 1 m of ...

[rmenurse]

In raising a 5000-N piano with a pulley system, for every 1 m of rope pulled down, the piano rises 0.1 m. Ideally, this means the force needed to lift the piano is
 
  A) 50 N.
  B) 500 N.
  C) 5000 N.
  D) not enough information

Question 2

An airplane flies 120 km at a constant altitude in a direction 30.0 north of east. A wind is blowing that results in a net horizontal force on the plane due to the air of 2.40 kN in a direction 10.0 south of west.
 
  How much work is done on the plane by the air? A) -2.71  108 J
  B) -0.985  108 J
  C) -221  108 J
  D) 221  108 J
  E) 0.821  108 J

[javimendoza7]

Answer to Question 1

Answer: B

Answer to Question 2

A

[rmenurse]

Thanks

[javimendoza7]

Welcome