MAH-MHT CET (PCM/PCB) entrance exam Question Bank Solutions for Physics

An organ pipe P₁ closed at one end vibrating in its first overtone and another pipe P₂ open at both ends vibrating in third overtone are in resonance with a given tuning fork. The ratio of the length of P₁ to that of P₂ is ______.

In a series resonant circuit, having L, C and R as its elements, the resonant current is i. The power dissipated in circuit at resonance is ______.

When source of sound moves towards a stationary observer, the wavelength of sound received by him ______.

A pipe closed at one end has length 83 cm. The number of possible natural oscillations of air column whose frequencies lie below 1000 Hz are ______. (velocity of sound in air = 332 m/s)

The closed and open organ pipes have same length. When they are vibrating simultaneously in first overtone, produce three beats. The length of open pipe is made `1/3` rd and closed pipe is made three times the original, the number of beats produced will be ______.

Two uniform wires of the same material are vibrating under the same tension. If the first overtone of the first wire is equal to the second overtone of the second wire and radius of the first wire is the twice the radius of the second wire, then the ratio of the lengths of the first wire to second wire is ______.

The fundamental frequency of an air column is a pipe closed at one end is 100 Hz. If the same pipe is open at both the ends, the frequencies produced in Hz are ______.

The observer is moving with velocity 'v₀' towards the stationary source of sound and then after crossing moves away from the source with velocity 'v₀'. Assume that the medium through which the sound waves travel is at rest. If v is the velocity of sound and n is the frequency emitted by the source, then the difference between apparent frequencies heard by the observer is ______.

The maximum frequency of transmitted radio waves above which the radio waves are no longer reflected back by ionosphere is ______.

(N = maximum electron density of lonosphere, g = acceleration due to gravity)

If the end correction of an open pipe is 0.8 cm, then the inner radius of that pipe will be ______.

The bob of a simple pendulum performs SHM with period T in air and with period T₁ in water Relation between T and T₁ is ______.

(neglect friction due to water, density of the material of the bob is = `9/8xx10^3` kgm³, density of water = 1 gcc^-1) 

In LC parallel resonance circuit, choose the correct statement.

A pipe P_c closed at one end and point P_o open at both ends are vibrating in the second overtone. They are in resonance with a given tuning fork. The ratio of the length of pipe P_c to that of pipe, P_o is ______.

(Neglect end correction).

The ratio of frequencies of two oscillating pendulums is 3 : 2. Their lengths are in the ratio.

The pitch of the whistle of an engine appears to drop by 20% of its original value when it passes a stationary observer. If the speed of sound in the air is 350 m/s, then the speed of the engine (in m/s) is ______.

A pendulum bob is swinging in a vertical plane, such that its angular amplitude is less than 90°. At its highest point, the string is cut. Which trajectory is possible for bob afterwards?

An open pipe is in resonance in its 2nd harmonic with tuning fork of frequency f₁. Now, it is closed at one end. If the frequency of the tuning fork is increased slowly from f₁, then again a resonance is obtained with a frequency f₂. If in this case the pipe vibrates nth harmonic, then ______.

Two organ pipes are emitting their fundamental notes, when each closed at end, give 5 beats per sec. If their fundamental frequencies are 250 Hz and 255 Hz, then find the ratio of their lengths.

Two weights w₁ and w₂ are suspended from the ends of light string over a smooth fixed pulley. If the pulley is pulled up with acceleration g, the tension in the string will be ______.

An organ pipe closed at one end resonates with a tuning fork of frequencies 180 Hz and 300 Hz. It will also resonate with tuning fork of frequency ______.