HSSC-1 (Class-11) Solved Physics MCQs; Unit-7: Oscillation;  (New Book/KPK Text Board, Peshawar) With Verified Answers 


1. Tuning of a radio set is an example of




... Answer is C. Electrical resonance
 -------------------------


2. The heating and cooking of food evenly by a microwave oven is an example of:




... Answer is B. Resonance
-------------------------


3. The time period of the same pendulum at Karachi and Murree is related as




... Answer is C. Tₖ ＜ Tₘ
The equation for Time Period T = 2𝝿 `\sqrt frac {L}{g}` 👉 shows that Time Period is inversely proportional to the square root of g 👉 Value of g is slightly greater at Karachi (Elevation = 10 m) than at Murree (Elevation = = 2300 m)(as the value of g depends on height) 👉 Keeping the same pendulum (no change in length) Tₖ will be less than Tₘ


4. In an isolated system the total energy of the vibrating mass and spring is:




... Answer is D. Constant
Law of conservation of energy


5. While deriving the equation of time period for a simple pendulum which quantity should be kept small:




... Answer is B. Amplitude
---------------------------


6. If the period of oscillation of mass (M) suspended from a spring is 2s, then the period of mass 4M will be




... Answer is D. 4 s
 Equation for Time Period of mass attached to spring T = 2𝝿 `\sqrt frac {M}{K}` = 2 s 👉 When M' = 4M then 👉 T' = 2𝝿 `\sqrt frac {4M}{K}` = 2𝝿 x 2 `\sqrt frac {M}{K}` = 2 (2𝝿 `\sqrt frac {M}{K}`) = 2 (2 s) = 4 s


7. The time period of a simple pendulum is 2 seconds. If its length is increased by 4 times then its period becomes :




... Answer is D. 4 s
Equation for Time Period of mass attached to spring T = 2𝝿 `\sqrt frac {L}{g}` = 2 s 👉 When L' = 4L then 👉 T' = 2𝝿 `\sqrt frac {4L}{g}` = 2𝝿 x 2 `\sqrt frac {L}{g}` = 2 (2𝝿 `\sqrt frac {L}{g}`) = 2 (2 s) = 4 s


8. To make the frequency double of a sprig oscillation, we have to:




... Answer is A. Reduce the mass to one fourth
 Given: f = `\ frac {1}{T}` = 1/2𝝿 `\sqrt frac {K}{m}` 👉 When f' = 2f then 👉 1/2𝝿`\sqrt frac {K}{m'}` = 2(1/2𝝿) `\sqrt frac {K}{m}` 👉 `\sqrt frac {K}{m'}` = 2 `\sqrt frac {K}{m}` 👉 taking square root both side and simplifying we get m' = `\ frac {1}{4}` m


9. The restoring force of SHM is maximum when the particle:




... Answer is A. Displacement is maximum
Hook's Law 👉 Applied Force F ∝ displacement x


10. Two springs of spring constants k₁ and k₂ are joined in series. The effective spring constant of the combination is given by




... Answer is C. Electrical resonance
 Hook's Law F = k₁x₁ = k₂x₂ 👉 k₁x₁ = k₂x₂ 👉 x₁ = `\ frac {k₂x₂}{k₁}` 👉 For both spring F = Kₑq (x₁ + x₂) 👉 Substituting value of x₁ 👉 F = Kₑq (`\ frac {k₂x₂}{k₁}` + x₂) 👉 substituting for F ( in term of spring 2) 👉 k₂x₂ = Kₑq (`\ frac {k₂x₂}{k₁}` + x₂) 👉 k₂ = Kₑq (`\ frac {k₂}{k₁}` + 1) Or 👉 Kₑq = k₁k₂/(k₁ + k₂)



Try the Above MCQs as a Quiz ( Click Here to Play the Quiz )

************************************

Shortcut Links For 


1. Website for School and College Level Physics   
2. Website for School and College Level Mathematics  
3. Website for Single National Curriculum Pakistan - All Subjects Notes 

© 2022-Onwards by Academic Skills and Knowledge (ASK)     

Note:  Write to me in the comment box below for any query and also Share this information with your class-fellows and friends.