11.

The old age arteries carrying blood in the human body become barrow resulting in an increase in blood pressure. This follows from

• Pascal's law

• Stoke's law

• Bernoulli's principle

• Archimedes principle

An organ pipe closed at one end has a fundamental frequency of 1500 Hz. The maximum number of overtones generated by this pipe which a normal can hear is

• 14

• 13

• 6

• 9

The Magnetic Resonance Imaging (MRI) is based on the phenomenon of

• nuclear magnetic resonance

• electron spin resonance

• electron paramagnetic resonance

• diamagnetism of human tissues

N  moles of a monoatomic gas is carried round the reversible rectangular cycle ABCDA as shown in the diagram. The temperature at A  is T_o. The thermodynamic efficiency of the cycle is

• 15 %

• 50 %

• 20 %

• 25 %

v_rms , v_av  and v_mp are root mean square, average and most probable speeds of molecules of a gas obeying Maxwellian velocity distribution. Which of the following statements is correct?

• v_rms <  v_av  < v_mp

• v_rms > v_av >  v_mp

• v_mp > v_rms > v_av

• v_mp > v_rms > v_av

Assertion: In a pressure cooker the water  is brought to boil. The cooker is then removed from the stove. Now on removing the lid of the pressure cooker, the water starts boiling again. 

Reason: The impurities in water bring down its boiling point.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion: Smaller drops of liquid resist deforming forces better than the larger drops. 

Reason: Excess pressure inside a drop is directly proportional to its surface area

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If assertion is true but reason is false

Assertion: The melting point of ice decreases with increase of pressure. 

Reason: Ice contracts on melting

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion: Thermodynamic process in nature are irreversible.

Reason: Dissipative effects cannot be eliminated.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

A proton and an  $\mathrm{\alpha }$ -particle, moving with the same velocity, enter into a uniform magnetic field, acting normal to the plane of their motion. The ratio of the radii of the circular paths described by the proton $\mathrm{\alpha }$-particle is

• 1 : 2

• 1 : 4

• 1 : 16

• 4 : 1