Welcome To My School Study
Class 9 Science MCQs on Freezing Point of Water, Force, Neutron Discovery, Acceleration, and Muscle Tissue with explanations.
Do You Know
Q1. Freezing point of water is:
Correct Answer: 0°C
Detailed Explanation
The freezing point of water is the temperature at which liquid water changes into solid ice. Under normal atmospheric pressure, water freezes at 0°C. At this temperature, both ice and water can exist together in equilibrium. This is an important physical property of water.
Important NCERT Points
- Water freezes at 0°C under normal atmospheric pressure.
- Freezing is a change of state from liquid to solid.
- During freezing, heat is released to the surroundings.
- The temperature remains constant during the change of state.
Exam-Oriented Fact
0°C is equal to 273 K on the Kelvin scale.
Quick Revision Line
Water freezes and changes into ice at 0°C.
Q2. Force can change:
Correct Answer: All of these
Detailed Explanation
A force can change the shape, speed, and direction of an object. It can also stop a moving object or make a stationary object move. Therefore, force affects the state of motion as well as the shape of objects. This makes force an important concept in physics.
Important NCERT Points
- Force can change the speed of an object.
- Force can change the direction of motion.
- Force can change the shape and size of an object.
- Force is a push or pull acting on an object.
Exam-Oriented Fact
The SI unit of force is Newton (N).
Quick Revision Line
Force can change an object’s shape, speed, and direction.
Q3. Neutron was discovered by:
Correct Answer: Chadwick
Detailed Explanation
The neutron was discovered by James Chadwick in 1932. Neutrons are electrically neutral particles found in the nucleus of an atom. Chadwick’s discovery helped scientists understand atomic structure more clearly and contributed greatly to nuclear physics.
Important NCERT Points
- James Chadwick discovered the neutron in 1932.
- Neutrons have no electric charge.
- They are present in the nucleus of atoms.
- Neutrons and protons together form the atomic nucleus.
Exam-Oriented Fact
The mass of a neutron is nearly equal to the mass of a proton.
Quick Revision Line
James Chadwick discovered the neutron in 1932.
Q4. Acceleration is:
Correct Answer: Vector
Detailed Explanation
Acceleration is the rate of change of velocity with time. Since velocity has both magnitude and direction, acceleration also has magnitude and direction. Therefore, acceleration is a vector quantity. It can be positive, negative, or zero depending on the motion of an object.
Important NCERT Points
- Acceleration is the change in velocity per unit time.
- It has both magnitude and direction.
- Acceleration is a vector quantity.
- SI unit of acceleration is m/s².
Exam-Oriented Fact
Negative acceleration is commonly called retardation or deceleration.
Quick Revision Line
Acceleration is a vector quantity measured in m/s².
Q5. Muscle tissue helps in:
Correct Answer: Movement
Detailed Explanation
Muscle tissue is responsible for movement in the body. It contracts and relaxes to move different body parts. Muscles also help maintain posture and support body functions such as breathing and blood circulation. There are three main types of muscle tissues: skeletal, smooth, and cardiac muscles.
Important NCERT Points
- Muscle tissue enables body movement.
- It works through contraction and relaxation.
- Skeletal muscles are attached to bones.
- Cardiac muscles are found in the heart.
Exam-Oriented Fact
Cardiac muscle works continuously throughout life without fatigue under normal conditions.
Quick Revision Line
Muscle tissue helps in the movement of the body.
One-Line Revision Sheet
- Water freezes at 0°C under normal atmospheric pressure.
- Force can change an object’s shape, speed, and direction.
- James Chadwick discovered the neutron in 1932.
- Acceleration is a vector quantity measured in m/s².
- Muscle tissue is responsible for body movement.
Related Links
- Class 9 MCQ Questions Answers– History, Geography, Civics
- Class 9 SST MCQs with Detailed Explanations
Latest Posts
- Class 10 Science MCQs with Answers | Light & Electricity
- Class 7 Science: Heat, Temperature, Conductors
- Class 9 Science MCQ Quiz: Matter, Motion, Work, Ions and Tissues
- Class 8 Science MCQ: Friction, Fluid Friction
- Class 8 Science MCQ Quiz: Reproduction & Hormones
Join Our Other Communities
