MATTER & CHEMISTRY
What subatomic particle determines the identity of an element?
Proton
What is the SI unit of force?
Newton (N)
What organelle is known as the powerhouse of the cell?
Mitochondrion
What is the star at the center of our solar system?
Sun
What is the unit of electric current?
Ampere (A)
An atom has 17 protons and 18 electrons. What is its charge?
−1
What force pulls objects toward Earth's surface?
Gravity
What process allows plants to convert light energy into chemical energy?
Photosynthesis
What causes day and night on Earth?
Earth's rotation
Which electromagnetic wave has a higher frequency: ultraviolet or visible light?
Ultraviolet
An element has atomic number 12 and mass number 24. How many neutrons does it have?
12
A 10-kg object experiences a net force of 50 N. What is its acceleration?
5 m/s²
Which blood vessels carry blood away from the heart?
Arteries
What layer of Earth's atmosphere is where most weather occurs?
Troposphere
What law describes the relationship between voltage, current, and resistance in an electrical circuit?
Ohm's Law
An atom has 13 protons, 14 neutrons, and 10 electrons. What is its overall charge?
+3
A car travels 200 m in 10 seconds. What is its average speed?
20 m/s
What structure in the lungs is the primary site of oxygen and carbon dioxide exchange?
Alveoli
Why do we experience different seasons?
Earth's axial tilt as it revolves around the Sun
What phenomenon occurs when a wave bends as it passes from one medium into another because its speed changes?
Refraction
🔥 An unknown ion has 20 protons, 20 neutrons, and 18 electrons. Identify the element, its charge, and its mass number.
An unknown ion has 20 protons, 20 neutrons, and 18 electrons. Identify the element, its charge, and its mass number.
A 4-kg object accelerates at 3 m/s². If the applied force is 20 N, what opposing force is acting on it?
Fnet=ma Fnet=4(3)=12N
A plant is kept in complete darkness for several days. Predict what will happen to its ability to produce glucose and explain why.
Its photosynthesis will greatly decrease or stop because light energy is required for photosynthesis.
What type of plate boundary is associated with plates moving toward each other?
Convergent boundary
What type of circuit has only one path for electric current to flow?
Series circuit