Physics: Concepts and Physics: Concepts and ConnectionsConnections, 4, 4thth ed., ed.,

Art Hobson Art Hobson

Ch. 6 – Conservation of EnergyCh. 6 – Conservation of Energy

A 1-kg book is lifted to a height of A 1-kg book is lifted to a height of 10 m. How much work is done on 10 m. How much work is done on

the book?the book?

A) NoneA) None

B) 1 JB) 1 J

C) 10 JC) 10 J

D) 100 JD) 100 J

E) 1000 JE) 1000 J

A 10 kg meteor moves through A 10 kg meteor moves through outer space (where g = 0). How outer space (where g = 0). How much work is done on the meteor much work is done on the meteor as it moves a distance of 5 m ?as it moves a distance of 5 m ?

A) NoneA) None

B) 2 JB) 2 J

C) 20 JC) 20 J

D) 50 JD) 50 J

E) 500 JE) 500 J

What happens to the gravitational What happens to the gravitational potential energy of a book when it is potential energy of a book when it is

lifted up to a height of 1.0 m ?lifted up to a height of 1.0 m ?

A) GravE increasesA) GravE increases

B) GravE decreasesB) GravE decreases

C) GravE stays about the sameC) GravE stays about the same

What happens to the gravitational What happens to the gravitational potential energy of a satellite that is potential energy of a satellite that is moved from an orbit that is 6000 km moved from an orbit that is 6000 km above the surface of the Earth to an above the surface of the Earth to an

orbit at an altitude of 12 000 km?orbit at an altitude of 12 000 km?Note: RNote: REarthEarth = 6370 km = 6370 km

A) GravE increasesA) GravE increases

B) GravE decreasesB) GravE decreases

C) GravE stays about the sameC) GravE stays about the same

What happens to the gravitational What happens to the gravitational force acting on a satellite that is force acting on a satellite that is

moved from an orbit that is 6000 km moved from an orbit that is 6000 km above the surface of the Earth to an above the surface of the Earth to an

orbit at an altitude of 12 000 km?orbit at an altitude of 12 000 km?Note: RNote: REarthEarth = 6370 km = 6370 km

A) The weight decreases by a factor of 4A) The weight decreases by a factor of 4

B) The weight decreases by a factor of 2B) The weight decreases by a factor of 2

C) The weight of the satellite stays the sameC) The weight of the satellite stays the same

In the demonstration with balls rolling In the demonstration with balls rolling down three different tracks, which track down three different tracks, which track

results in the largest final speed?results in the largest final speed?

A) The “high road” (convex)A) The “high road” (convex)

B) The “middle road” (straight path)B) The “middle road” (straight path)

C) The “low road” (concave)C) The “low road” (concave)

D) The final speed is the same for all three.D) The final speed is the same for all three.