8th Grade Quiz Questions And Answers

Explanation
The statement is true because a meteorologist is indeed a scientist who specializes in studying and forecasting the weather. They use various tools and techniques to analyze atmospheric conditions, climate patterns, and weather phenomena. Their expertise helps in understanding and predicting weather events, which is crucial for various industries and sectors such as agriculture, aviation, and disaster management.

Explanation
The given statement is incorrect. The barometer is not a device used to measure temperature. It is actually a device used to measure atmospheric pressure. Temperature is typically measured using a thermometer.

Explanation
The statement correctly defines fluids as substances that flow freely and take the shape of their container. This definition aligns with the properties commonly associated with fluids, such as liquids and gases. Therefore, the answer "True" is correct.

Explanation
The scale of absolute temperature is the Kelvin Scale. This scale is based on the absolute zero point, which is the lowest possible temperature at which all molecular motion ceases. The Kelvin scale is used in scientific and engineering applications because it is an absolute scale, meaning it does not use any arbitrary reference points like the Celsius or Fahrenheit scales. In the Kelvin scale, the temperature is measured in kelvins, with 0 K representing absolute zero.

Explanation
Cohesion refers to the ability of molecules of the same kind of matter to stick together. This property is responsible for the formation of drops, surface tension, and the capillary action in liquids. It is the cohesive forces between water molecules that allow water to form droplets and maintain its shape. Cohesion is an essential property for many biological processes, such as the transportation of water in plants through the xylem vessels. Adhesion, on the other hand, refers to the ability of different molecules to stick together, while buoyancy is the upward force exerted on an object submerged in a fluid.

Explanation
Adhesion refers to the ability of molecules of different kinds of matter to stick together. This phenomenon occurs due to intermolecular forces such as hydrogen bonding or van der Waals forces. Adhesion is responsible for various processes in nature, such as water sticking to the surface of a leaf or the ability of paint to adhere to a wall. It is different from cohesion, which refers to the ability of molecules of the same substance to stick together. Buoyancy, on the other hand, is the upward force exerted by a fluid on an object immersed in it.

Explanation
John Dalton is the correct answer because he was a British scientist who developed the atomic theory of matter. His theory proposed that all matter is composed of small indivisible particles called atoms, and that atoms of different elements have different properties. Dalton's atomic theory laid the foundation for modern chemistry and our understanding of the composition and behavior of matter.

Explanation
Daniel Bernoulli is the correct answer because he was a Swiss mathematician who made significant contributions to the kinetic theory of matter. He developed the principle known as Bernoulli's principle, which explains the relationship between the speed of a fluid and its pressure. His work laid the foundation for understanding the behavior of particles in gases and fluids, which is a fundamental aspect of the kinetic theory of matter.

Explanation
The correct answer is Kinetic theory of matter. The kinetic theory of matter states that the molecules of matter are in constant motion. This theory explains that the particles in a substance are constantly moving and colliding with each other. It also explains the relationship between temperature and the speed of the particles. The kinetic theory of matter is a fundamental concept in understanding the behavior and properties of matter.

Explanation
The normal atmospheric pressure is 14.7 psi because this value represents the average pressure exerted by the Earth's atmosphere at sea level. Atmospheric pressure is caused by the weight of the air above and around us, and it decreases with increasing altitude. 14.7 psi is considered standard atmospheric pressure and is commonly used as a reference point for various measurements and calculations.