Class 9 Motion Puzzles
1. What is the unit of speed in the SI system?
- a) metre
- b) metre per second
- c) kilometer
- d) kilometer per hour
Hint: Speed is defined as distance traveled per unit of time.
Answer: b) metre per second
2. What is the term for motion along a straight line?
- a) Circular motion
- b) Linear motion
- c) Non-uniform motion
- d) Uniform motion
Hint: This type of motion occurs when an object moves along a straight path.
Answer: b) Linear motion
3. Which law states that an object will remain at rest or in uniform motion unless acted upon by an external force?
- a) Newton's First Law
- b) Newton's Second Law
- c) Newton's Third Law
- d) Newton's Law of Universal Gravitation
Hint: This law is also known as the law of inertia.
Answer: a) Newton's First Law
4. What is the velocity of an object that covers 100 meters in 10 seconds?
- a) 10 m/s
- b) 50 m/s
- c) 100 m/s
- d) 5 m/s
Hint: Velocity is equal to distance divided by time.
Answer: a) 10 m/s
5. What type of motion occurs when an object moves in a circular path?
- a) Linear motion
- b) Circular motion
- c) Rotational motion
- d) Vibrational motion
Hint: This motion occurs in objects moving around a central point.
Answer: b) Circular motion
6. The formula for acceleration is:
- a) (Final velocity - Initial velocity) / Time
- b) (Initial velocity - Final velocity) / Time
- c) Distance / Time
- d) Speed / Time
Hint: Acceleration is the change in velocity over time.
Answer: a) (Final velocity - Initial velocity) / Time
7. What type of motion involves an object moving at a constant speed?
- a) Non-uniform motion
- b) Uniform motion
- c) Accelerated motion
- d) Circular motion
Hint: The object covers equal distances in equal time intervals.
Answer: b) Uniform motion
8. What is the unit of acceleration in the SI system?
- a) m/s
- b) m/s²
- c) km/h²
- d) m²/s
Hint: Acceleration is the rate of change of velocity per unit time.
Answer: b) m/s²
9. According to Newton's second law of motion, force is equal to:
- a) Mass times velocity
- b) Mass times acceleration
- c) Mass divided by acceleration
- d) Velocity divided by time
Hint: Force is the product of mass and acceleration.
Answer: b) Mass times acceleration
10. What does Newton's third law of motion state?
- a) For every action, there is an equal and opposite reaction.
- b) An object at rest stays at rest unless acted upon.
- c) Force is equal to mass times acceleration.
- d) Motion is always in a straight line.
Hint: This law explains the reaction forces when you push something.
Answer: a) For every action, there is an equal and opposite reaction.