Work and Energy

Which sequence describes the energy conversions

in a car’s engine?

• chemical to thermal to mechanical

• mechanical to thermal to chemical

• thermal to mechanical to chemical

• kinetic to potential to mechanical

Tags

NGSS.HS-PS3-3

What is the potential energy of a 10.0 kg weight suspended 3.0 m above the ground?

• 3.3 J

• 30 J

• 290 J

• 2900J

Tags

NGSS.MS-PS3-2

What is the kinetic energy of a 1000 kg car traveling at 20 m/s _______.

• 200000 J

• 20000 J

• 400000 J

• 20000000 J

Tags

NGSS.MS-PS3-1

According to the law of conservation of energy

• energy cannot be created or destroyed

• everything eventually stops moving

• potential energy must be converted into kinetic energy

• kinetic energy plus potential energy equals mechanical energy

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

The gravitational potential energy of a cucumber

Earth system changes when which factor changes?

• the cucumber's speed

• the cucumber's mass

• the cucumber's temperature

• the cucumber's length

Tags

NGSS.MS-PS2-4

NGSS.MS-PS3-2

Which cannot be done by a machine?

• increase force

• increase work

• change direction of a force

• increase velocity

Which factor increases as the efficiency of a

machine increases?

• work input

• work output

• friction

• input force

Friction causes mechanical energy to be

converted into which form?

• thermal energy

• kinetic energy

• nuclear energy

• potential energy

Tags

NGSS.MS-PS3-5

What term indicates the number of times a machine multiplies the input force?

• efficiency

• power

• mechanical advantage

• resistance

Tags

NGSS.MS-ETS1-2

The kinetic energy from an object’s motion

always changes when which factor changes

• the object's chemical potential energy

• the objects volume

• the object's direction of motion

• the object's speed

Tags

NGSS.MS-PS3-1