SIFT Physics and Simple Machines 2 ā Questions and Answers
Question 1: A pulley system has a mechanical advantage of 4. If a 200 N load is lifted, how much effort force is required (ignoring friction)?
- 50 N (Correct answer)
- 100 N
- 800 N
- 200 N
Correct answer: 50 N
Mechanical advantage = Load / Effort, so Effort = 200 N / 4 = 50 N.
Question 2: Which type of lever has the fulcrum located between the effort and the load?
- First-class lever (Correct answer)
- Second-class lever
- Third-class lever
- Compound lever
Correct answer: First-class lever
In a first-class lever, the fulcrum is positioned between the effort force and the load.
Question 3: An inclined plane reduces the force needed to lift an object by increasing which quantity?
- The distance over which force is applied (Correct answer)
- The weight of the object
- Gravitational acceleration
- The normal force
Correct answer: The distance over which force is applied
An inclined plane trades increased distance for reduced force, allowing the same work to be done with less effort.
Question 4: A wheel and axle has a wheel radius of 30 cm and an axle radius of 5 cm. What is its mechanical advantage?
- 6 (Correct answer)
- 0.17
- 150
- 25
Correct answer: 6
MA of a wheel and axle = wheel radius / axle radius = 30 / 5 = 6.
Question 5: Newton's Second Law states that force equals mass times acceleration. If a 10 kg object accelerates at 3 m/sĀ², what net force acts on it?
- 30 N (Correct answer)
- 3.3 N
- 13 N
- 0.3 N
Correct answer: 30 N
F = ma = 10 kg Ć 3 m/sĀ² = 30 N.
Question 6: Which of the following best describes potential energy?
- Energy stored due to position or configuration (Correct answer)
- Energy of motion
- Energy released as heat
- Energy transferred by waves
Correct answer: Energy stored due to position or configuration
Potential energy is stored energy based on an object's position or configuration, such as gravitational or elastic potential energy.
Question 7: A wedge is a modified version of which simple machine?
- Inclined plane (Correct answer)
- Lever
- Pulley
- Wheel and axle
Correct answer: Inclined plane
A wedge is essentially two inclined planes joined back-to-back and converts a downward force into horizontal splitting forces.
SIFT Physics and Simple Machines 2
A pulley system has a mechanical advantage of 4.
If a 200 N load is lifted, how much effort force is required (ignoring friction)?