| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.41 |
| Score | 0% | 68% |
Materials like metals that transfer heat efficiently are called:
reflectors |
|
conductors |
|
insulators |
|
refractors |
Heat is always transferred from warmer to cooler environments and conduction is the simplest way this transfer can occur. It is accomplished through direct contact between materials and materials like metals that transfer heat efficiently are called conductors while those that conduct heat poorly, such as plastic, are called insulators.
Force is measured in newtons (N) with 1 N being the force required to impart an acceleration of:
1 m/s2 to a mass of 1 kg/s2 |
|
1 mph to a mass of 1 kg |
|
1 m/s2 to a mass of 1 kg |
|
1 m/s to a mass of 1 kg |
Weight is a force that describes the attraction of gravity on an object. Force is measured in newtons (N) with 1 N being the force required to impart an acceleration of 1 m/s2 to a mass of 1 kg.
Acceleration is the rate of change of velocity per unit of time. Which of these is the formula for acceleration?
\(\vec{a} = { \Delta \vec{v} \over t }\) |
|
\(\vec{a} = { \vec{v} \over t }\) |
|
\(\vec{a} = \Delta \vec{v} t \) |
|
\(\vec{a} = { t \over \Delta \vec{v} }\) |
Acceleration is the rate of change of velocity per unit of time. In physics, the delta symbol (\(\Delta\)) represents change so the formula for acceleration becomes \(\vec{a} = { \Delta \vec{v} \over t }\)
Which of the following is related to the Cambrian Explosion?
first civilizations |
|
carbon dating |
|
fossil record |
|
extinction of dinosaurs |
The Cambrian period is one of the most significant geological time periods. Lasting about 53 million years, it marked a dramatic burst of changes in life on Earth known as the Cambrian Explosion. It is from this period that the majority of the history of life on Earth, as documented by fossils, is found. Called the fossil record, the layering of these mineralized imprints of organisms preserved in sedementary rock have allowed geologists to build a historical record of plant and animal life on Earth.
Which of these is not a component of blood?
plasma |
|
red blood cells |
|
white blood cells |
|
marrow |
Blood is created in bone marrow and is made up of cells suspended in liquid plasma. Red blood cells carry oxygen, white blood cells fight infection, and platelets are cell fragments that allow blood to clot.