Question

3.1 assessment
match each description on the left with the type of energy it best matches on the right. each type of energy may be used only once.

1. —— objects, hot objects, and volcanoes
2. —— water at the top of a waterfall
3. —— wind, river flow, and waves
4. —— sunlight
5. —— trees, batteries, and natural gas
6. —— fusion and fission

type of energy
a. solar energy
b. potential energy
c. nuclear energy
d. kinetic energy
e. thermal energy
f. chemical energy

1. which parts of the human body rely on electrical signals to work?

i. heart
ii. muscles
iii. eyes
a. i and ii only
b. i and iii only
c. ii and iii only
d. i, ii, and iii

1. how does a capacitive touch - sensitive screen work on a tablet?

a. the pressure from a touch command completes an electrical pathway.
b. when the user’s finger touches the screen, a tiny electrical charge passes through it to complete an electrical pathway.
c. the pressure from a touch command generates a magnetic field.
d. when the user’s finger touches the screen, a flexible plastic expands and contracts.

1. what causes a maglev train to levitate?

a. electrical coils create magnetic fields that repel large magnets under the train
b. nuclear propulsion
c. upward jets of compressed air
d. antigravitational acceleration

1. scientists have developed a plastic that expands and contracts slightly in response to electrical energy. what has this enabled scientists to build?

a. maglev trains
b. capacitive touch - sensitive screens
c. photovoltaic cells
d. robots with human - like hand and facial movements

1. you stir some cream into a cup of warm coffee with a spoon. what types of energy are evident in this example?

a. kinetic and thermal energy
b. potential and kinetic energy
c. kinetic, thermal, and chemical energy
d. kinetic, thermal, and mechanical energy

1. what type of reactions occur in the sun?

a. solar reactions
b. fusion reactions
c. fission reactions
d. thermal reactions

1. thermal energy is generated through the rapid motion of the particles that make up an object. based on this description, what other type of energy could thermal energy be classified as?

a. potential energy
b. kinetic energy
c. mechanical energy
d. chemical energy

1. which of the following types of energy is released by forming new atoms?

a. nuclear energy
b. chemical energy
c. atomic energy
d. formation energy

Explanation:

To solve these questions, we analyze each one based on the relevant scientific concepts:

Question 7

The human body parts that rely on electrical signals to work:

• I (Heart): The heart's pacemaker cells generate electrical signals to regulate heartbeats.
• II (Muscles): Muscle contractions are triggered by electrical signals from nerves.
• III (Eyes): The retina and optic nerve use electrical signals to transmit visual information.

So all three (I, II, III) rely on electrical signals.

Answer:

D. I, II, and III

Question 8

How a capacitive touch - sensitive screen works:

• Capacitive touch screens work by detecting the change in the electrical field when a conductive object (like a finger) touches the screen. When the user's finger touches the screen, a tiny electrical charge passes through it to complete an electrical pathway. Option B correctly describes this mechanism. Option A is incorrect as it's not about pressure completing a pathway. Option C is incorrect as capacitive screens don't use magnetic fields. Option D is incorrect as capacitive screens don't involve the expansion and contraction of flexible plastic.