2.1.3

A second skydiver is still in the airplane, waiting to jump. He accidentally drops his helmet out the door of the plane. Complete the sentence to describe how the energy of the helmet changes as it falls to Earth. Right before it hits the ground, the helmet will have the maximum amount of ________ and the minimum amount of _______.

• GPE, KE

• KE, GPE

Answer explanation

As velocity increases, KE increases. Right before hitting Earth, the velocity and KE of the helmet will both be at their maximum.

As height decreases, GPE decreases. Right before hitting Earth, the helmet's height and GPE will both be close to zero.

Tags

NGSS.MS-PS3-2

NGSS.MS-PS3-5

Which equation describes how total energy (E_total) and mechanical energy (ME) are related for this pendulum?

• E_total = ME − PE

• E_total = ME + KE + PE

• E_total = ME

• E_total = ME − KE

Answer explanation

For the pendulum in this simulation, the total energy (E_total) is equal to the mechanical energy (ME).

Tags

NGSS.MS-PS3-4

Which three statements about energy are true?

• Energy can move among the different parts of an isolated system.

• A closed system can lose energy to its surroundings.

• Energy can be transformed from one type into another.

• New energy can be created within an open system.

Answer explanation

Energy can be transformed and transferred, but it cannot be created or destroyed.

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

What happens to the total mechanical energy of the pendulum when there is friction in the pendulum system?

• The mechanical energy decreases over time.

• The mechanical energy increases over time.

• The mechanical energy stays constant.

Answer explanation

The mechanical energy of the pendulum steadily decreases over time due to friction.

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

Which blood component helps clot the blood?

• Leukocytes

• Erythrocytes

• Thrombocytes

• Plasma

What part of the eye is a clear protective structure that allows light to enter the eye?

• iris

• retina

• cornea

• choroid

This condition occurs when the valves are pushed inward

• Tricuspid valve prolapse

• Cardiac tamponade

• Mitral valve prolapse

• Myocardial infarction

What part is #2?

• Pinna

• Ear Canal

• Ear Drum

• Oval Window

What part is ?

• Semicircular Canals

• Eustachian Tube

• Cochlea

• Oval Window

The instrument used to examine eyes.

• otoscope

• opthalmoscope

• hysteroscope

• microscope