Title: Pre-Unit Assessment
Course: MNPCC Physics > Section: Energy

Use this quiz to see where you are at going into the unit.

Q: The following diagram shows a the path of a pendulum.  At what point does the pendulum have the highest gravitational potential energy?
- Position A and C are equivalent. (Correct)
- Position A (Position C is equivalent)
- Position B (Being at the lowest point, it has the least GPE.)
- Position C (A and C are equivalent.)
A: Position A and C are equivalent.
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: The following diagram shows a the path of a pendulum.  At what point does the pendulum have the highest kinetic energy?
- Position A and C are equivalent. (They are equivalent, but not the highest.)
- Position A (A and C have the least.)
- Position B (Correct.)
- Position C (A and C are equivalent with the least.)
A: Position B
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: The diagram below shows 3 possible forces that are identical in magnitude on a box that is moving to the right.  Which force would be doing the most amount of work on the box?
- Force C (Correct.)
- Force B (As this is only partially in the direction of motion, it does less work than C.)
- Force A (Since this force is perpendicular to the direction of motion, it does no work.)
- All 3 are identical. (The forces are identical, but that does not mean the amount of work they do is, direction matters.)
A: Force C
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: Which statement best describes what a wind turbine does in terms of energy?
- The wind turbine transforms energy from the air into electrical energy. (Correct.)
- The air moves the turbine creating electrical energy. (Energy cannot be created or destroyed.)
- The moving fan blades harvest the electrical energy from the air. (There is no electrical energy in the air.)
A: The wind turbine transforms energy from the air into electrical energy.
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: How does the energy needed to change a cars velocity from 0 to 20 m/s compare to 0 to 10 m/s?
- 0 to 20 m/s requires 4 times the energy. (Correct.)
- 0 to 20 m/s requires twice as much energy. (Kinetic energy is related to velocity squared.)
- 0 to 20 m/s requires 10 times the energy. (Kinetic energy is related to velocity squared.)
A: 0 to 20 m/s requires 4 times the energy.
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: How does the energy required to lift a book from the floor to 1 m up compare to lifting the book from the floor to 2 m up?
- Lifting 2 m up requires twice the energy. (Correct.)
- Lifting 2 m up requires 4 times the energy. (Energy is proportional to height.)
- Lifting 2 m up requires 1.5 times the energy. (Energy is proportional to height.)
A: Lifting 2 m up requires twice the energy.
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: Which has more thermal energy, an iceberg with a mass of 10 million metric tons and a temperature of -5 °C or a 0.5 kg cup of coffee at 90 °C
- The iceberg. (Correct.)
- The coffee. (The mass is way more important than the temperature.)
- They are roughly equal since both are mostly made of water. (The mass and temperature are pretty important as well.)
A: The iceberg.
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: How do the amount of works compare for each of the following scenarios.

1. Holding a 10 kg brick 1 m above the floor.
2. Lifting a 10 kg brick 1 m above the floor.
3. Walking at a constant speed for 1 m while holding a 10 kg brick 1 m above the floor.
- Situation 2 requires the most work. (Correct)
- Situation 1 requires the most work. (Your force is not in the direction of motion.)
- Situation 3 requires the most work. (Your force is not in the direction of motion.)
A: Situation 2 requires the most work.
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: Two containers of water, A and B, are being stirred at the same rate.  A is stirred for twice as long as B.  How does the temperature change of the two compare assuming they are both perfectly thermally insulated from their surroundings?
- A's change in temperature will be twice as big as B's. (Correct.)
- A's temperature change will be four times that of B. (Temperature change is related linearly to energy put in.)
- They will have the same positive temperature change. (A will change more as it is being stirred longer.)
- They will have the same negative temperature change. (Energy is being put in, not taken out.)
- Neither will change temperature. (Energy is being added, with no other form to go to.)
A: A's change in temperature will be twice as big as B's.
If right: Your answer is correct.
If wrong: Your answer is incorrect.

Q: Two student jump with equal force.  Student A pushes on the floor while rising 0.1 m. Student B pushes on the floor while rising 0.2 m.  Who will jump higher?
- Student B (Correct.)
- Student A. (Distance matters.)
- They will jump the same height. (Distance matters.)
A: Student B
If right: Your answer is correct.
If wrong: Your answer is incorrect.