What is Impulse ? : āĻ āĻāĻŋāĻāĻžāϤ
What is Impulse ?
Impulse is the change in momentum of an object. āĻ
āĻāĻŋāĻāĻžāϤ āĻšā§āĻā§ āĻā§āύ⧠āĻŦāϏā§āϤā§ā§° āĻā§°āĻŦā§āĻā§° āĻĒā§°āĻŋāĻŦāϰā§āϤāύāĨ¤ When a force acts on an object for a certain time, the momentum of the object changes. āϝā§āϤāĻŋāϝāĻŧāĻž āĻā§āύ⧠āĻŦāϏā§āϤā§ā§° āĻāĻĒā§°āϤ āĻāĻŋāĻā§ āϏāĻŽāϝāĻŧ āϧ⧰āĻŋ āĻŦāϞ āĻĒā§ā§°āϝāĻŧā§āĻ āĻšāϝāĻŧ, āϤā§āϤāĻŋāϝāĻŧāĻž āĻŦāϏā§āϤā§āĻā§ā§° āĻā§°āĻŦā§āĻ āĻĒā§°āĻŋāĻŦāϰā§āϤāύ āĻšāϝāĻŧāĨ¤
Before and After / āĻāĻāϤ⧠āĻā§°ā§ āĻĒāĻŋāĻāϤ
- Before force → Initial momentum (āĻŦāϞ āĻĒā§ā§°āϝāĻŧā§āĻā§° āĻāĻāϤ⧠→ āĻĒā§ā§°āĻžā§°āĻŽā§āĻāĻŋāĻ āĻā§°āĻŦā§āĻ)
- After force → Final momentum (āĻŦāϞ āĻĒā§ā§°āϝāĻŧā§āĻā§° āĻĒāĻŋāĻāϤ → āĻā§āĻĄāĻŧāĻžāύā§āϤ āĻā§°āĻŦā§āĻ)
Force acting over time changes momentum. (āϏāĻŽāϝāĻŧ āϧ⧰āĻŋ āĻŦāϞ āĻĒā§ā§°āϝāĻŧā§āĻā§ āĻā§°āĻŦā§āĻ āĻĒā§°āĻŋāĻŦāϰā§āϤāύ āĻā§°ā§āĨ¤)
Formula of Impulse / āĻ āĻāĻŋāĻāĻžāϤ⧰ āϏā§āϤā§ā§°
Impulse = F × t
Where / āϝ’āϤ, F = Force / āĻŦāϞ , t = Time / āϏāĻŽāϝāĻŧ
Impulse depends on force and time. (āĻ āĻāĻŋāĻāĻžāϤ āĻŦāϞ āĻā§°ā§ āϏāĻŽāϝāĻŧā§° āĻāĻĒā§°āϤ āύāĻŋā§°ā§āĻā§° āĻā§°ā§āĨ¤)
Important Points / āĻā§ā§°ā§āϤā§āĻŦāĻĒā§āϰā§āĻŖ āĻāĻĨāĻž
- More force → More impulse (āĻ āϧāĻŋāĻ āĻŦāϞ → āĻ āϧāĻŋāĻ āĻ āĻāĻŋāĻāĻžāϤ)
- More time → More impulse (āĻ āϧāĻŋāĻ āϏāĻŽāϝāĻŧ → āĻ āϧāĻŋāĻ āĻ āĻāĻŋāĻāĻžāϤ)
- Change in momentum = Impulse (āĻā§°āĻŦā§āĻā§° āĻĒā§°āĻŋāĻŦāϰā§āϤāύ = āĻ āĻāĻŋāĻāĻžāϤ)
SI Unit / SI āĻāĻāĻ : SI unit of impulse = Newton-second (N·s) (āĻ āĻāĻŋāĻāĻžāϤ⧰ SI āĻāĻāĻ = āύāĻŋāĻāĻāύ-āĻā§āĻā§āĻŖā§āĻĄ (N·s))
- Impulse: āĻ āĻāĻŋāĻāĻžāϤ = Formula & When to Use : āϏā§āϤā§ā§° āĻā§°ā§ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° : Click Here
- Why is impulse important in daily life ? āĻĻā§āύāύā§āĻĻāĻŋāύ āĻā§ā§ąāύāϤ āĻ āĻāĻŋāĻāĻžāϤ āĻāĻŋāϝāĻŧ āĻā§ā§°ā§āϤā§āĻŦāĻĒā§āϰā§āĻŖ ? : Click Here
Impulse – PYQ MCQ : āĻ āĻāĻŋāĻāĻžāϤ – PYQ MCQ
1. What is impulse ? āĻ āĻāĻŋāĻāĻžāϤ āĻāĻŋ ?
A) Change in velocity B) Change in momentum C) Change in force D) Change in mass
Ans: B) Change in momentum
Explanation: Impulse is the change in momentum of an object. (āĻ āĻāĻŋāĻāĻžāϤ āĻšā§āĻā§ āĻŦāϏā§āϤā§ā§° āĻā§°āĻŦā§āĻā§° āĻĒā§°āĻŋāĻŦāϰā§āϤāύāĨ¤)
2. Impulse depends on: āĻ āĻāĻŋāĻāĻžāϤ āĻāĻŋāĻšā§° āĻāĻĒā§°āϤ āύāĻŋā§°ā§āĻā§° āĻā§°ā§ ?
A) Mass and speed B) Force and time C) Heat and pressure D) Density and volume
Ans: B) Force and time
Explanation: Impulse increases with force and time. (āĻŦāϞ āĻā§°ā§ āϏāĻŽāϝāĻŧ āĻŦā§āĻĻā§āϧāĻŋ āĻĒāĻžāϞ⧠āĻ āĻāĻŋāĻāĻžāϤ⧠āĻŦā§āĻĻā§āϧāĻŋ āĻĒāĻžāϝāĻŧāĨ¤)
3. Formula of impulse is: āĻ āĻāĻŋāĻāĻžāϤ⧰ āϏā§āϤā§ā§° āĻā§āύāĻā§ ?
A) P = mv B) F = ma C) Impulse = F × t D) W = mg
Ans: C) Impulse = F × t
Explanation: Impulse equals force multiplied by time. (āĻ āĻāĻŋāĻāĻžāϤ = āĻŦāϞ × āϏāĻŽāϝāĻŧāĨ¤)
4. SI unit of impulse is: āĻ āĻāĻŋāĻāĻžāϤ⧰ SI āĻāĻāĻ āĻāĻŋ ?
A) Joule B) Newton C) Newton-second D) Watt
Ans: C) Newton-second
Explanation: SI unit of impulse is N·s. āĻ āĻāĻŋāĻāĻžāϤ⧰ SI āĻāĻāĻ āĻšā§āĻā§ N·sāĨ¤
5. When force acts for a longer time, impulse becomes: āĻŦāϞ āĻ āϧāĻŋāĻ āϏāĻŽāϝāĻŧ āϧ⧰āĻŋ āĻĒā§ā§°āϝāĻŧā§āĻ āĻšāϞ⧠āĻ āĻāĻŋāĻāĻžāϤ āĻāĻŋ āĻšāϝāĻŧ ?
A) Smaller B) Zero C) Greater D) Constant
Ans: C) Greater
Explanation: Impulse is directly proportional to time. (āĻ āĻāĻŋāĻāĻžāϤ āϏāĻŽāϝāĻŧā§° āϏā§āϤ⧠āϏāĻŽāĻžāύā§āĻĒāĻžāϤāĻŋāĻāĨ¤)
6. Impulse causes change in: āĻ āĻāĻŋāĻāĻžāϤ⧠āĻāĻŋāĻšā§° āĻĒā§°āĻŋāĻŦāϰā§āϤāύ āĻāĻāĻžāϝāĻŧ ?
A) Mass B) Density C) Momentum D) Volume
Ans: C) Momentum
Explanation: Impulse changes the momentum of an object. (āĻ āĻāĻŋāĻāĻžāϤ⧠āĻŦāϏā§āϤā§ā§° āĻā§°āĻŦā§āĻ āĻĒā§°āĻŋāĻŦāϰā§āϤāύ āĻā§°ā§āĨ¤)
7. A large force acting for short time can produce: āĻ āϞā§āĻĒ āϏāĻŽāϝāĻŧā§° āĻŦāĻžāĻŦā§ āĻŦā§āĻšā§ āĻŦāϞ⧠āĻāĻŋ āĻā§āĻĒāύā§āύ āĻā§°āĻŋāĻŦ āĻĒāĻžā§°ā§ ?
A) Small impulse B) Large impulse C) Zero impulse D) Constant impulse
Ans: B) Large impulse
Explanation: Large force gives large impulse even in short time. (āĻŦā§āĻšā§ āĻŦāϞ⧠āĻāĻŽ āϏāĻŽāϝāĻŧāϤ⧠āĻ āϧāĻŋāĻ āĻ āĻāĻŋāĻāĻžāϤ āĻā§āĻĒāύā§āύ āĻā§°āĻŋāĻŦ āĻĒāĻžā§°ā§āĨ¤)
8. Impulse is equal to: āĻ āĻāĻŋāĻāĻžāϤ āĻāĻŋāĻšā§° āϏāĻŽāĻžāύ ?
A) Change in momentum B) Speed C) Mass D) Velocity
Ans: A) Change in momentum
Explanation: Impulse and change in momentum are equal. (āĻ āĻāĻŋāĻāĻžāϤ āĻā§°ā§ āĻā§°āĻŦā§āĻā§° āĻĒā§°āĻŋāĻŦāϰā§āϤāύ āϏāĻŽāĻžāύāĨ¤)
9. Catching a ball with soft hands increases: āύāϰāĻŽ āĻšāĻžāϤā§ā§°ā§ āĻŦāϞ āϧ⧰āĻŋāϞ⧠āĻāĻŋ āĻŦā§āĻĻā§āϧāĻŋ āĻĒāĻžāϝāĻŧ ?
A) Force B) Time of contact C) Mass D) Speed
Ans: B) Time of contact
Explanation: Increasing time reduces force during catching. āϏāĻŽāϝāĻŧ āĻŦā§āĻĻā§āϧāĻŋ āĻĒāĻžāϞ⧠āĻŦāϞ⧰ āĻŽāĻžāύ āĻāĻŽā§āĨ¤
10. Find impulse when force = 5 N and time = 2 s. (āĻŦāϞ = 5 N āĻā§°ā§ āϏāĻŽāϝāĻŧ = 2 s āĻšāϞ⧠āĻ āĻāĻŋāĻāĻžāϤ āύāĻŋā§°ā§āĻŖāϝāĻŧ āĻā§°āĻžāĨ¤)
A) 7 N·s B) 8 N·s C) 10 N·s D) 12 N·s
Ans: C) 10 N·s
Explanation: Impulse = F × t
Impulse(āĻ āĻāĻŋāĻāĻžāϤ) = 5 × 2 = 10 N·s
11. A force of 10 N acts on an object for 2 s. Find impulse. (10 N āĻŦāϞ⧠āĻāĻāĻž āĻŦāϏā§āϤā§ā§° āĻāĻĒā§°āϤ 2 s āϏāĻŽāϝāĻŧ āϧ⧰āĻŋ āĻā§āϰāĻŋāϝāĻŧāĻž āĻā§°āĻŋāĻā§āĨ¤ āĻ āĻāĻŋāĻāĻžāϤ āύāĻŋā§°ā§āĻŖāϝāĻŧ āĻā§°āĻžāĨ¤)
Soln
Formula / āϏā§āϤā§ā§°: Impulse = Force(F)× Time(T) (āĻ āĻāĻŋāĻāĻžāϤ = āĻŦāϞ × āϏāĻŽāϝāĻŧ)
Force (F) = 10 N, Time (t) = 2 s
Impulse = F x T = 10 × 2 = 20 N·s
Ans / āĻāϤā§āϤ⧰: Impulse = 20 N·s (āĻ āĻāĻŋāĻāĻžāϤ = 20 N·s)
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2 Marks Questions : ⧍ āύāĻŽā§āĻŦā§°ā§° āĻĒā§āϰāĻļā§āύ
1. What is impulse ? āĻ āĻāĻŋāĻāĻžāϤ āĻāĻŋ ?
5 Marks Questions : ā§Ģ āύāĻŽā§āĻŦā§°ā§° āĻĒā§āϰāĻļā§āύ