Laws of Motion: Class 11 Physics Q&A
17 free answers on Laws of Motion (Physics) for Class 11 students, across CBSE, ICSE and State boards. Includes questions such as “What is the difference between petrol and diesel engine?”, “How do you calculate velocity from momentum?”, “How do you find acceleration with force, mass, and angle?”
Question & Answer
Questions
- PhysicsClass 11All
What is the difference between petrol and diesel engine?
Petrol (gasoline) engines and diesel engines are two common types of internal combustion engines, each with its own set of characteristics. Here are five key differences between petrol and diesel engines: Fuel Type: Petrol Engine: Petrol engines use gasoline (petrol) as their fuel. Gasoline is a lighter fuel compared to diesel and is more volatile. Diesel Engine: Diesel engines use diesel fuel, which is heavier and has a higher energy density than gasoline. Diesel is l
- PhysicsClass 11All
How do you calculate velocity from momentum?
Use the momentum formula rearranged: v = p/m where p is momentum (in kg·m/s) and m is mass (in kg). This is one of the simplest velocity calculations. Remember: Momentum = mass × velocity, so velocity = momentum ÷ mass Both momentum and velocity are vectors (have direction) Units must be consistent: if p is in kg·m/s and m in kg, v will be in m/s Example: A 6
- PhysicsClass 11All
How do you find acceleration with force, mass, and angle?
Finding acceleration when force is applied at an angle requires decomposing the force into components aligned with your coordinate system, then applying a = F_net / m to the relevant component. If a 100 N force pulls a 20 kg sled at 30° above horizontal, the horizontal component is F_x = 100 cos(30°) = 86.6 N and the vertical component is F_y = 100 sin(30°) = 50 N. For horizontal acceleration (assuming frictionless ice), a_x = 86.6 / 20 = 4.33 m/s². The verti
- PhysicsClass 11All
What is the law of acceleration of Newton? What is its formula and use?
Newton's second law of acceleration states that the net force acting on an object equals its mass multiplied by its acceleration, expressed as F_net = ma or rearranged to a = F_net / m. This law establishes the quantitative relationship between force (cause) and acceleration (effect), revealing that acceleration is directly proportional to applied force and inversely proportional to mass. A 10 N force produces 10 m/s² acceleration on a 1 kg object, 5 m/s
- PhysicsClass 11All
How to derive acceleration from momentum
Deriving acceleration from momentum uses the relationship between force, momentum change, and Newton's second law. Momentum is defined as p = mv (mass times velocity), so a change in momentum is Δp = m·Δv when mass is constant. Newton's second law states F = ma, but it can also be expressed as F = Δp / Δt (force equals rate of momentum change). Combining these gives ma = Δp / &Delt
- PhysicsClass 11All
What are the 3 laws of Newton?
Newton's three laws are: (1) Law of Inertia an object remains at rest or in uniform motion unless acted upon by a force(2) Law of Acceleration force equals mass times acceleration (F = ma), meaning greater force produces greater acceleration(3) Law of Action Reaction for every action, there's an equal and opposite reaction. These laws form the foundation of classical mechanics and explain everything from why seatbelts save lives to how rockets propel thro
- PhysicsClass 11All
What is F·ΔT (F triangle T)?
F·ΔT or F×Δt represents impulse, the product of force and the time interval over which it acts. Impulse euals the change in momentum: F·Δt = ΔP = mv - mu. This concept is essential in understanding collisions and impacts. A large force acting for a short time (like a hammer blow) can produce the same momentum change as a small force acting for a long time.
- PhysicsClass 11All
How much is 100 dyne?
100 dynes euals 0.001 newtons or 10⁻³ N. To convert, use the relationship: 1 dyne = 10⁻⁵ newtons. Therefore, 100 dynes = 100 × 10⁻⁵ N = 10⁻³ N = 0.001 N. This is a very small force roughly euivalent to the weight of about 0.1 grams under Earth's gravity.
- PhysicsClass 11All
What is 1 dyne in CGS?
In the CGS (centimeter-gram-second) system, 1 dyne is defined as 1 g·cm/s², meaning it's the force reuired to accelerate a 1-gram mass at 1 centimeter per second suared. This is the fundamental definition within the CGS system, making dyne the base unit of force in this measurement framework, just as the newton is for the SI system.
- PhysicsClass 11All
Which unit is dyne?
Dyne is a unit of force in the centimeter-gram-second (CGS) system of units. It's abbreviated as "dyn." One dyne is the force needed to give a mass of 1 gram an acceleration of 1 cm/s². While largely replaced by the newton in modern physics, dyne remains useful in certain applications, particularly in measuring very small forces.
- PhysicsClass 11All
What is 1 dyne eual to?
One dyne euals 10⁻⁵ newtons or 1 g·cm/s². It's the CGS unit of force, defined as the force reuired to accelerate a mass of one gram at a rate of one centimeter per second suared. While the newton is the standard SI unit today, dyne is still occasionally used in specialized fields like surface tension measurements.
- PhysicsClass 11All
Is dyne the SI unit of momentum?
No, dyne is not the SI unit of momentum. Dyne is the CGS unit of force, not momentum. The SI unit of momentum is kilogram meter per second (kg·m/s). However, in the CGS system, momentum is measured in gram centimeter per second (g·cm/s), which can also be expressed as dyne-seconds since 1 dyne·s = 1 g·cm/s.
- PhysicsClass 11All
What is the value of Δt?
The value of Δt de The expression (mv - mu)/t represents force according to Newton's Second Law, where m is mass, v is final velocity, u is initial velocity, and t is time. This can be rewritten as m(v - u)/t = ma, showing the relationship between force, mass, and acceleration. It also demonstrates that force euals the rate of change of momentum: F = ΔP/Δt. pends on the specific situation being analyzed. It represents a time interval or change in time between two mom
- PhysicsClass 11All
What is 2 g's of force?
2g means experiencing twice Earth's normal gravity, or 19.6 m/s² of acceleration. You might feel this briefly in a fast elevator starting upward, on certain roller coasters, or in a sports car accelerating hard. At 2g, a 70 kg person feels like they weigh 140 kg. While uncomfortable and reuiring effort to move, 2g is sustainable for most healthy people for extended periods without special euipment.
- PhysicsClass 11All
What is 1 G to 1 kg?
1g applied to 1 kg produces a force of 9.8 Newtons. The relationship is F = m × a, where mass (1 kg) multiplied by acceleration (9.8 m/s² or 1g) euals 9.8 N of force. This is the fundamental conversion between gravitational acceleration and the force it produces on a mass. Each additional g-force multiplies this: 2g on 1 kg = 19.6 N, 3g = 29.4 N, and so on.
- PhysicsClass 11All
Is 1 kgf eual to 1 kg?
No, 1 kgf (kilogram-force) euals 9.8 Newtons, while 1 kg is a unit of mass. The kilogram-force is a non-SI unit representing the force exerted by 1 kg mass under standard gravity (9.8 m/s²). So, 1 kgf = 1 kg × 9.8 m/s² = 9.8 N. While the SI system uses Newtons for force and kilograms for mass, some fields still use kgf, which can cause confusion since the numbers appear similar.
- PhysicsClass 11All
How much is 1 g-force?
1 g-force euals 9.8 m/s² of acceleration or 9.8 N/kg of specific force. This is the acceleration you experience standing still on Earth's surface. In terms of feeling, 1g is your normal weight—what you experience every moment. It's used as a baseline: 2g feels twice as heavy, 0.5g feels half as heavy, and 0g is weightlessness.