Explore topic-wise MCQs in Physics.

This section includes 32 Mcqs, each offering curated multiple-choice questions to sharpen your Physics knowledge and support exam preparation. Choose a topic below to get started.

1.

A large tank filled with water to a height ?h? is to be emptied through a small hole at the bottom. The ratio of time taken for the level of water to fall from h to \[\frac{h}{2}\] and from \[\frac{h}{2}\] to zero is    [EAMCET (Engg.) 2003]

A. \[\sqrt{2}\]   
B. \[\frac{1}{\sqrt{2}}\]  
C. If assertion is true but reason is false.
D. \[\frac{1}{\sqrt{2}-1}\]
Answer» D. \[\frac{1}{\sqrt{2}-1}\]
2.

The diagram shows a cup of tea seen from above. The tea has been stirred and is now rotating without turbulence. A graph showing the speed v with which the liquid is crossing points at a distance X from O along a radius XO would look like

A.  
B.  
C. \[\sqrt{\frac{{{k}_{1}}}{{{k}_{2}}}}\] 
D.  
Answer» E.
3.

Which graph represents the variation of surface tension with temperature over small temperature ranges for water

A.  
B.   
C. \[mgR\frac{{{n}^{2}}}{{{n}^{2}}+1}\]
Answer» C. \[mgR\frac{{{n}^{2}}}{{{n}^{2}}+1}\]
4.

The weight of a body is 9.8 N at the place where g = 9.8 \[m{{s}^{-2}}\]. Its mass is [NDA]

A. zero  
B. 9.8 kg
C. Depends upon the direction of projection
D. 1kg
Answer» E.
5.

  An astronaut in the orbit in a spacecraft feels weightlessness

A. due to the absence of gravity inside
B. due to the face that space craft has no energy
C. \[\sqrt{\frac{2GM}{{{R}^{3}}}}\]
D. their is no gravity outside
Answer» D. their is no gravity outside
6.

  Why do two ice blocks join to form one block when pressed together? [NDA]

A. Melting point of ice is lowered with increase in pressure
B. Melting point of ice increases with increase in pressure
C. \[9{{V}_{e}}\]
D. Melting point of ice is \[0{}^\circ C\]
Answer» B. Melting point of ice increases with increase in pressure
7.

  When a ship floats on water   [NDA]

A. it displaces no water
B. the mass of water displaced is equal to the mass of the ship
C. 11.2 km/sec
D. the mass of water displaced is greater than the mass of the ship
Answer» E.
8.

  Dirty cloths containing grease and oil stains are cleaned by adding detergents to water. Stains are removed because detergent  [CDS]

A. reduces drastically the surface tension between water and oil
B. increases the surface tension between water and oil
C. Zero
D. decreases the viscosity in detergent mixed water
Answer» B. increases the surface tension between water and oil
9.

  A liquid is kept in a regular cylindrical vessel up to a certain height. If this vessel is replaced by another cylindrical vessel having half the area of cross-section of the bottom, the pressure on the bottom will    [CDS]

A. remain unaffected
B. be reduced to half the earlier pressure
C. I and IV
D. be reduced to one-fourth the earlier pressure
Answer» B. be reduced to half the earlier pressure
10.

  Flow velocities in an incompressible fluid can be measured with which one of the following?  [NDA]

A. Barometer  
B. Venturi tube
C. R/4
D. Manometer
Answer» C. R/4
11.

  Assertion: The value of 'g' is greater at the equator than at the poles. Reason: Radius is more at the equator than at the poles.

A. If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
B. If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
C. \[\frac{mgR}{2}\]
D. If Assertion is incorrect but Reason is correct.
Answer» E.
12.

  The substance which exhibits practically no elastic effect is

A. rubber 
B. quartz
C. Increase by 2%
D. Cu
Answer» C. Increase by 2%
13.

An artificial satellite orbiting the earth does not fall down because the earth's attraction

A. is balanced by the attraction of the moon
B. vanishes at such distances
C. \[{{R}^{5/2}}\] 
D. produces the necessary acceleration of its motion in a curved path
Answer» E.
14.

If the radius of the earth were to shrink by one percent, its mass remaining the same, the value of g on the earth's surface would: [IAS Prelim]

A. increase by 0.5%
B. increase by 2%
C. If assertion is true but reason is false.
D. decrease by 2%
Answer» C. If assertion is true but reason is false.
15.

A liquid flows in a tube from left to right as shown in figure. \[{{A}_{1}}\] and \[{{A}_{2}}\] are the cross-sections of the portions of the tube as shown. Then the ratio of speeds \[{{v}_{1}}/{{v}_{2}}\] will be

A. \[{{A}_{1}}/{{A}_{2}}\]
B. \[{{A}_{2}}/{{A}_{1}}\]
C. If assertion is true but reason is false.
D. \[\sqrt{{{A}_{1}}}/\sqrt{{{A}_{2}}}\]
Answer» C. If assertion is true but reason is false.
16.

In a laminar flow the velocity of the liquid  in contact with the walls of the tube is

A. Zero
B. Maximum 
C. If assertion is true but reason is false.
D. Equal to critical velocity
Answer» B. Maximum 
17.

A square plate of 0.1 m side moves parallel to a second plate with a velocity of 0.1 m/s, both plates being immersed in water. If the viscous force is 0.002 N and the coefficient of viscosity is 0.01 poise, distance between the plates in m is [EAMCET  (Med.) 2003]

A. 0.1 
B. 0.05
C. Increases
D. 0.0005
Answer» E.
18.

In which one of the following cases will the liquid flow in a pipe be most streamlined    [Pb. CET 2005]

A. Liquid of high viscosity and high density flowing through a pipe of small radius
B. Liquid of high viscosity and low density flowing through a pipe of small radius
C. \[\frac{g}{4}\]
D. Liquid of low viscosity and high density flowing through a pipe of large radius
Answer» C. \[\frac{g}{4}\]
19.

A block of ice floats on a liquid of density 1.2in a beaker then level of liquid when ice completely melt  [IIT-JEE 1994]

A. Remains same
B. Rises
C. dR 
D. (a), (b) or (c)
Answer» C. dR 
20.

Two capillaries made of same material but of different radii are dipped in a liquid. The rise of liquid in one capillary is 2.2 cm and that in the other is 6.6 cm. The ratio of their radii is     [MP PET 1990]

A. 0.37569444444444
B.  1 : 9
C. 72 N   
D.  1 : 3
Answer» D.  1 : 3
21.

Water rises up to a height h in a capillary tube of certain diameter. This capillary tube is replaced by a similar tube of half the diameter. Now the water will rise to the height of [Kerala PMT 2005]

A. 4h 
B. 3h
C. Will remain the same  
D. H
Answer» D. H
22.

Radius of a capillary is \[2\times {{10}^{-3}}m.\] A liquid of weight \[6.28\times {{10}^{-4}}N\] may remain in the capillary then the surface tension of liquid will be     [RPET 2003]

A. \[5\times {{10}^{-3}}N/m\] 
B. \[5\times {{10}^{-2}}N/m\]
C. \[\frac{{{g}_{1}}}{{{g}_{2}}}=\frac{R_{1}^{2}}{R_{2}^{2}}\] 
D.  \[50\,N/m\]
Answer» C. \[\frac{{{g}_{1}}}{{{g}_{2}}}=\frac{R_{1}^{2}}{R_{2}^{2}}\] 
23.

In the state of weightlessness, a capillary tube is dipped in water, then water

A. Will not rise at all
B. Will rise to same height as at atmospheric pressure
C. 1   
D.   Will rise up to the upper end of the capillary tube of any length
Answer» E.
24.

The action of a nib split at the top is explained by     [JIPMER 1999]

A. Gravity flow
B.  Diffusion of fluid
C. \[x=\frac{h}{2}\] 
D. Osmosis of liquid
Answer» D. Osmosis of liquid
25.

A vessel, whose bottom has round holes with diameter of 0.1mm, is filled with water. The maximum height to which the water can be filled without leakage is (S.T. of water =75 dyne/cm, g =1000 cm/s2) [CPMT 1989; J&K CET 2004]

A. 100 cm
B.   75 cm
C.  
D. 30 cm
Answer» E.
26.

Assertion   :   Terminal velocity is same as the critical velocity. Reason     : The constant velocity of fall of a body through a viscous fluid is called terminal velocity.

A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
C. 10 kg
D. If the assertion and reason both are false.
E. If assertion is false but reason is true.
Answer» F.
27.

Assertion   :   A rain drop after falling through some height attains a constant velocity. Reason     : At constant velocity, the viscous drag is just equal to its weight.

A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
C. because acceleration in the orbit is equal to acceleration of gravity outside
D. If the assertion and reason both are false.
E. If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
28.

Assertion   :   A fluid flowing out of a small hole in a vessel apply a backward thrust on the vessel. Reason     : According to equation of continuity, the product of area and velocity remain constant.

A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
C. Melting point of ice remains unchanged with increase in pressure
D. If the assertion and reason both are false.
E. If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
29.

Assertion   :   The water rises higher in a capillary tube of small diameter than in the capillary tube of large diameter. Reason   : Height through which liquid rises in a capillary tube is inversely proportional to the diameter of the capillary tube.

A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
C. the mass of water displaced is lesser than the mass of the ship
D. If the assertion and reason both are false.
E. If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
30.

Assertion   :   It is easier to spray water in which some soap is dissolved. Reason   : Soap is easier to spread.

A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
C. increases the viscosity of water and oil
D. If the assertion and reason both are false.
E. If assertion is false but reason is true.
Answer» D. If the assertion and reason both are false.
31.

A liquid is coming out from a vertical tube. The relation between the weight of the drop W, surface tension of the liquid T and radius of the tube r is given by, if the angle of contact is zero

A. \[W=\pi {{r}^{2}}T\]
B.  \[W=2\pi rT\]
C. be increased to twice the earlier pressure
D. \[W=\frac{3}{4}\pi {{r}^{3}}T\]
Answer» C. be increased to twice the earlier pressure
32.

A liquid does not wet the sides of a solid, if the angle of contact is  [MP PAT 1990; AFMC 1988;  MNR 1998; RPMT 1999, 2003; Pb. PMT 2002 KCET 2005]

A. Zero
B.  Obtuse (More than\[90{}^\circ \])   
C. Strain gauge
D. \[90{}^\circ \]
Answer» C. Strain gauge