ASVAB General Science Practice Test 996988

Questions 5
Topics Kelvin Scale, Mass vs. Weight, Medulla, Secondary Consumers, Vectors

Study Guide

Kelvin Scale

In contrast to the Celsius scale (measured in degrees centigrade) that fixes 0° at the freezing point of water and the Fahrenheit scale that uses 32°, the Kelvin scale fixes 0° at absolute zero (-273°C) which is the lowest temperature possible in the universe.

Mass vs. Weight

Mass is the amount of matter something has while weight is the force exerted on an object's mass by gravity. So, although a person's mass doesn't change when going from the Earth to the Moon, their weight will decrease because the force of the Moon's gravity is much less than that of Earth.

Medulla

Part of the brainstem, the medulla is the connection between the brain and the spinal cord. It controls involuntary actions like breathing, swallowing, and heartbeat.

Secondary Consumers

Secondary consumers (carnivores) subsist mainly on primary consumers. Omnivores are secondary consumers that also eat producers. Examples are rats, fish, and chickens.

Vectors

Velocity and displacement are vector quantities which means each is fully described by both a magnitude and a direction. In contrast, scalar quantities are quantities that are fully described by a magnitude only. A variable indicating a vector quantity will often be shown with an arrow symbol: \(\vec{v}\)