General Q&A for Class 12 · Page 193
5,215 free answers in General for Class 12 students, across CBSE, ICSE and State boards.
Question & Answer
Questions
- GeneralClass 12All
What is kinematics in 11th physics?
In Class 11 physics, kinematics forms the foundation of mechanics. Students learn to analyze motion in one and two dimensions, study concepts like displacement, velocity, and acceleration, and apply kinematic equations to solve real-world problems. The syllabus typically covers motion in a straight line, projectile motion, relative motion, and graphical analysis of motion. This builds essential problem-solving skills for advanced physics topics.
- GeneralClass 12All
What is a = (v - u) / t?
This formula defines acceleration as the rate of change of velocity. Here, 'a' is acceleration, 'v' is final velocity, 'u' is initial velocity, and 't' is time. It tells you how quickly an object's velocity changes. For example, if a car accelerates from 0 m/s (u) to 20 m/s (v) in 4 seconds (t), the acceleration is (20-0)/4 = 5 m/s². The formula rearranges to v = u + at, one of the primary kinematic equations.
- GeneralClass 12All
What formula is v² = u² + 2as?
This is the third equation of motion, connecting velocity and displacement without involving time. It's particularly useful when you know initial velocity (u), acceleration (a), and displacement (s), but need to find final velocity (v) or vice versa. For instance, if you drop a ball from rest (u=0) with gravity a=10 m/s² over a distance s=5m, the final velocity is v = √(0 + 2×10×5) = 10 m/s.
- GeneralClass 12All
What are the 5 key kinematics equations?
The five essential kinematics equations are: v = u + at (velocity-time relation) s = ut + ½at² (displacement-time relation) v² = u² + 2as (velocity-displacement relation) s = (u + v)t / 2 (average velocity relation) s = vt - ½at² (alternative displacement formula) Each equation uses different combinations of the five variables (u, v, a, t, s), allowing you to solve any kinematics problem w
- GeneralClass 12All
What are the 3 formulas of motion?
The three equations of motion, also called Newton's equations of kinematics, are: v = u + at, s = ut + ½at², and v² = u² + 2as. These were derived assuming constant acceleration and form the cornerstone of classical mechanics. They allow you to predict an object's position and velocity at any time, making them invaluable for everything from engineering calculations to space mission planning.
- GeneralClass 12All
What is the SI unit of kinematics?
Kinematics doesn't have a single SI unit since it involves multiple quantities. Displacement is measured in meters (m), velocity in meters per second (m/s), acceleration in meters per second squared (m/s²), and time in seconds (s). These SI base and derived units ensure consistency in calculations and allow scientists worldwide to communicate measurements clearly.
- GeneralClass 12All
What are the 7 basic units of physics?
The seven fundamental SI units are: meter (m) for length, kilogram (kg) for mass, second (s) for time, ampere (A) for electric current, kelvin (K) for temperature, mole (mol) for amount of substance, and candela (cd) for luminous intensity. All other physics units are derived from these base units. For example, velocity (m/s) combines meters and seconds.
- GeneralClass 12All
What is (mv - mu) / t?
This formula represents force according to Newton's second law. Here, 'm' is mass, 'v' is final velocity, 'u' is initial velocity, and 't' is time. The expression (mv - mu) represents change in momentum, so dividing by time gives the rate of change of momentum, which equals force (F = ma). This connects kinematics with dynamics, showing how motion relates to the forces causing it.
- GeneralClass 12All
What is 300 K to Celsius?
300 K converts to 26.85°C (approximately 27°C). This is a warm room temperature, typical of a comfortable indoor environment in warmer climates.
- GeneralClass 12All
What is 10 degrees Celsius equal to in K?
10°C equals 283.15 K. To calculate this, add 273.15 to the Celsius temperature: 10 + 273.15 = 283.15 K.
- GeneralClass 12All
Is 100°C equal to 373 K?
Yes, 100°C equals 373.15 K (often rounded to 373 K). This is the boiling point of water at standard atmospheric pressure. The conversion: 100 + 273.15 = 373.15 K.
- GeneralClass 12All
What is 25°C and 373°C in Kelvin?
25°C = 298.15 K (room temperature) 373°C = 646.15 K (very hot, well above water's boiling point) Note: 373 K equals 100°C (boiling point), not 373°C.
- GeneralClass 12All
What is 100°C in Kelvin?
100°C equals 373.15 K. This is the temperature at which water boils at sea level.
- GeneralClass 12All
What is 98.0°F in Celsius?
98.0°F equals approximately 36.7°C. This is slightly below the average body temperature and still within the normal range.
- GeneralClass 12All
What is zero Kelvin?
Zero Kelvin (0 K) is absolute zero, the lowest possible temperature in the universe. It equals -273.15°C or -459.67°F. At this temperature, all molecular motion theoretically stops. In practice, absolute zero cannot be reached, though scientists have gotten extremely close in laboratory conditions. It represents the point where matter contains minimal thermal energy.
- GeneralClass 12All
Why is 273 called absolute zero?
There's a common misconception here 273 is not absolute zero. Absolute zero is 0 Kelvin, which equals approximately -273°C (precisely -273.15°C). The number 273 appears in conversions because you add or subtract approximately 273 (precisely 273.15) when converting between Celsius and Kelvin scales.
- GeneralClass 12All
What is 98.6°F in Celsius?
98.6°F equals 37°C. This is the average normal human body temperature. The conversion formula from Fahrenheit to Celsius is: °C = (°F - 32) × 5/9.
- GeneralClass 12All
Is 98.6°F 37°C true or false?
True. 98.6°F equals 37°C, representing normal body temperature. More precisely, it's 36.89°C, but 37°C is the standard rounded value used in medical contexts.
- GeneralClass 12All
What is 273 Kelvin in Celsius?
273 Kelvin equals -0.15°C (or approximately 0°C). More precisely, 273.15 K equals exactly 0°C, which is the freezing point of water. The value 273 K is often used as a rounded approximation.
- GeneralClass 12All
What is 1 K equal to in Celsius?
1 Kelvin as an absolute temperature equals -272.15°C. This is extremely cold, just one degree above absolute zero. Remember, when converting individual temperatures (not temperature differences), you must subtract 273.15.