Motion, Forces And Energy

Question 1

What SI unit and common variables are associated with length?

Answer 1

Length or distance has SI units of meters (m).

Question 2

What SI unit and common variables are associated with acceleration?

Answer 2

Acceleration has SI units of meters/second2(m/s2).

Question 3

What SI unit and common variables are associated with time?

Answer 3

Time has SI units of seconds (s).

Question 4

What SI unit and common variables are associated with volume?

Answer 4

Volume has SI units of meters3(m3)

Question 5

What two characteristics are necessary to define a vector?

Answer 5

Magnitude and direction.

Question 6

Define:

magnitude of a vector

Answer 6

Magnitude is the quantity, size, or amount and is a scalar value since it lacks direction.

Question 7

Define:

direction of a vector

Answer 7

Direction provides spacial orientation, angle, or path.

Question 8

Explain how objects falling in a uniform gravitational field without air/liquid resistance undergo free fall:

Answer 8

• Acceleration due to gravity (g) causes constant acceleration downward.
• Velocity increases linearly over time.
• Displacement (distance fallen) increases quadratically over time.

Question 9

Explain how objects falling in a uniform gravitational field with air/liquid resistance experience more complex motion

Answer 9

• Initially accelerates due to gravity, but resistance force from the medium opposes this acceleration.
• As velocity increases, resistance force also increases until it balances gravitational force.
• Terminal velocity is reached when net force becomes zero, resulting in constant velocity.
• Terminal velocity depends on factors such as object’s mass, surface area, and medium density.

Question 10

Fossil Fuels (Chemical Energy):

Advantages:

Answer 10

• Abundant and easily accessible.
• Reliable and well-established technology.

Question 11

Fossil Fuels (Chemical Energy):

Disadvantages

Answer 11

• Non-renewable and finite resource.
• Releases greenhouse gases and pollutants when burned, contributing to climate change and air pollution.

Question 12

Describe Newton’s first law of motion

Answer 12

Law of Inertia: An object in motion will continue with constant velocity unless acted on by a net force.

Similarly, an object at rest will continue to remain at rest until acted on by a net force.

Question 13

What is the relationship between force, mass, and acceleration in Newton’s second law of motion?

Answer 13

Fnet = ma

Note: net force and acceleration are both vectors, and must be pointing in the same direction.

Question 14

How does Newton’s third law of motion describe the forces between two objects?

Answer 14

For every force from one object on a second, there is an equal and opposite force from the second back on the first.