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MCQOPTIONS
This section includes 12583 Mcqs, each offering curated multiple-choice questions to sharpen your Joint Entrance Exam - Main (JEE Main) knowledge and support exam preparation. Choose a topic below to get started.
| 4201. |
A body of mass \[{{m}_{1}}\]is moving with a velocity V. It collides with another stationary body of mass \[{{m}_{2}}.\] They get embedded. At the point of collision, the velocity of the system [DCE 1999, 2001] |
| A. | Increases |
| B. | Decreases but does not become zero |
| C. | Remains same |
| D. | Become zero |
| Answer» C. Remains same | |
| 4202. |
The quantity that is not conserved in an inelastic collision is [Pb. PMT 2000] |
| A. | Momentum |
| B. | Kinetic energy |
| C. | Total energy |
| D. | All of these |
| Answer» C. Total energy | |
| 4203. |
A mass of 20 kg moving with a speed of 10m/s collides with another stationary mass of \[5kg.\] As a result of the collision, the two masses stick together. The kinetic energy of the composite mass will be [MP PMT 2000] |
| A. | 600 Joule |
| B. | 800 Joule |
| C. | 1000 Joule |
| D. | 1200 Joule |
| Answer» C. 1000 Joule | |
| 4204. |
A neutron having mass of \[1.67\times {{10}^{-27}}kg\] and moving at \[{{10}^{8}}m/s\] collides with a deutron at rest and sticks to it. If the mass of the deutron is\[3.34\times {{10}^{-27}}kg\]then the speed of the combination is [CBSE PMT 2000] |
| A. | \[2.56\times {{10}^{3}}m/s\] |
| B. | \[2.98\times {{10}^{5}}m/s\] |
| C. | \[3.33\times {{10}^{7}}m/s\] |
| D. | \[5.01\times {{10}^{9}}m/s\] |
| Answer» D. \[5.01\times {{10}^{9}}m/s\] | |
| 4205. |
A body of mass 2kg is moving with velocity 10 m/s towards east. Another body of same mass and same velocity moving towards north collides with former and coalsces and moves towards north-east. Its velocity is [CPMT 1997; JIPMER 2000] |
| A. | 10 m/s |
| B. | 5 m/s |
| C. | 2.5 m/s |
| D. | \[5\sqrt{2}\,m/s\] |
| Answer» E. | |
| 4206. |
Which of the following is not a perfectly inelastic collision [BHU 1998; JIPMER 2001, 02; BHU 2005] |
| A. | Striking of two glass balls |
| B. | A bullet striking a bag of sand |
| C. | An electron captured by a proton |
| D. | A man jumping onto a moving cart |
| Answer» B. A bullet striking a bag of sand | |
| 4207. |
A metal ball of mass 2 kg moving with a velocity of 36 km/h has an head on collision with a stationary ball of mass 3 kg. If after the collision, the two balls move together, the loss in kinetic energy due to collision is [CBSE PMT 1997; AIIMS 2001] |
| A. | 40 J |
| B. | 60 J |
| C. | 100 J |
| D. | 140 J |
| Answer» C. 100 J | |
| 4208. |
If a skater of weight 3 kg has initial speed 32 m/s and second one of weight 4 kg has 5 m/s. After collision, they have speed (couple) 5 m/s. Then the loss in K.E. is [CPMT 1996] |
| A. | 48 J |
| B. | 96 J |
| C. | Zero |
| D. | None of these |
| Answer» E. | |
| 4209. |
A ball is dropped from height 10 m. Ball is embedded in sand 1 m and stops, then [AFMC 1996] |
| A. | Only momentum remains conserved |
| B. | Only kinetic energy remains conserved |
| C. | Both momentum and K.E. are conserved |
| D. | Neither K.E. nor momentum is conserved |
| Answer» B. Only kinetic energy remains conserved | |
| 4210. |
A moving body of mass m and velocity 3 km/h collides with a rest body of mass 2m and sticks to it. Now the combined mass starts to move. What will be the combined velocity [CBSE PMT 1996; JIPMER 2001, 02] |
| A. | 3 km/h |
| B. | 2 km/h |
| C. | 1 km/h |
| D. | 4 km/h |
| Answer» D. 4 km/h | |
| 4211. |
Two putty balls of equal mass moving with equal velocity in mutually perpendicular directions, stick together after collision. If the balls were initially moving with a velocity of \[45\sqrt{2}\,m{{s}^{-1}}\] each, the velocity of their combined mass after collision is [Haryana CEE 1996; BVP 2003] |
| A. | \[45\sqrt{2}\,m{{s}^{-1}}\] |
| B. | \[45\,m{{s}^{-1}}\] |
| C. | \[90\,m{{s}^{-1}}\] |
| D. | \[22.5\sqrt{2}\,m{{s}^{-1}}\] |
| Answer» C. \[90\,m{{s}^{-1}}\] | |
| 4212. |
A 50 g bullet moving with velocity 10 m/s strikes a block of mass 950 g at rest and gets embedded in it. The loss in kinetic energy will be [MP PET 1994] |
| A. | 100% |
| B. | 95% |
| C. | 5% |
| D. | 50% |
| Answer» C. 5% | |
| 4213. |
A bag (mass M) hangs by a long thread and a bullet (mass m) comes horizontally with velocity v and gets caught in the bag. Then for the combined (bag + bullet) system [CPMT 1989; Kerala PMT 2002] |
| A. | Momentum is \[\frac{mvM}{M+m}\] |
| B. | Kinetic energy is \[\frac{m{{v}^{2}}}{2}\] |
| C. | Momentum is \[\frac{mv(M+m)}{M}\] |
| D. | Kinetic energy is \[\frac{{{m}^{2}}{{v}^{2}}}{2(M+m)}\] |
| Answer» E. | |
| 4214. |
In the above question, if another body is at rest, then velocity of the compound body after collision is |
| A. | v/2 |
| B. | 2v |
| C. | v |
| D. | Zero |
| Answer» B. 2v | |
| 4215. |
A particle of mass m moving eastward with a speed v collides with another particle of the same mass moving northward with the same speed v. The two particles coalesce on collision. The new particle of mass 2m will move in the north-easterly direction with a velocity [NCERT 1980; CPMT 1991; MP PET 1999; DPMT 1999, 2005] |
| A. | v/2 |
| B. | 2v |
| C. | \[v/\sqrt{2}\] |
| D. | v |
| Answer» D. v | |
| 4216. |
A sample of metal weighs 210 gm in air, 180 gm in water and 120 gm in liquid. Then relative density (RD) of |
| A. | Metal is 3 |
| B. | Metal is 7 |
| C. | Liquid is 3 |
| D. | Liquid is \[\frac{1}{3}\] |
| Answer» D. Liquid is \[\frac{1}{3}\] | |
| 4217. |
A silver ingot weighing 2.1 kg is held by a string so as to be completely immersed in a liquid of relative density 0.8. The relative density of silver is 10.5. The tension in the string in kg-wt is |
| A. | 1.6 |
| B. | 1.94 |
| C. | 3.1 |
| D. | 5.25 |
| Answer» C. 3.1 | |
| 4218. |
A metallic block of density 5 gm cm?3 and having dimensions 5 cm × 5 cm × 5 cm is weighed in water. Its apparent weight will be |
| A. | 5 × 5 × 5 × 5 gf |
| B. | 4 × 4 × 4 × 4 gf |
| C. | 5 × 4 × 4 × 4 gf |
| D. | 4 × 5 × 5 × 5 gf |
| Answer» E. | |
| 4219. |
A cubical block is floating in a liquid with half of its volume immersed in the liquid. When the whole system accelerates upwards with acceleration of g/3, the fraction of volume immersed in the liquid will be |
| A. | \[\frac{1}{2}\] |
| B. | \[\frac{3}{8}\] |
| C. | \[\frac{2}{3}\] |
| D. | \[\frac{3}{4}\] |
| Answer» B. \[\frac{3}{8}\] | |
| 4220. |
In making an alloy, a substance of specific gravity \[{{s}_{1}}\] and mass \[{{m}_{1}}\] is mixed with another substance of specific gravity \[{{s}_{2}}\] and mass \[{{m}_{2}}\]; then the specific gravity of the alloy is [CPMT 1995] |
| A. | \[\left( \frac{{{m}_{1}}+{{m}_{2}}}{{{s}_{1}}+{{s}_{2}}} \right)\] |
| B. | \[\left( \frac{{{s}_{1}}{{s}_{2}}}{{{m}_{1}}+{{m}_{2}}} \right)\] |
| C. | \[\frac{{{m}_{1}}+{{m}_{2}}}{\left( \frac{{{m}_{1}}}{{{s}_{1}}}+\frac{{{m}_{2}}}{{{s}_{2}}} \right)}\] |
| D. | \[\frac{\left( \frac{{{m}_{1}}}{{{s}_{1}}}+\frac{{{m}_{2}}}{{{s}_{2}}} \right)}{{{m}_{1}}+{{m}_{2}}}\] |
| Answer» D. \[\frac{\left( \frac{{{m}_{1}}}{{{s}_{1}}}+\frac{{{m}_{2}}}{{{s}_{2}}} \right)}{{{m}_{1}}+{{m}_{2}}}\] | |
| 4221. |
A hemispherical bowl just floats without sinking in a liquid of density 1.2 × 103kg/m3. If outer diameter and the density of the bowl are 1 m and 2 × 104 kg/m3 respectively, then the inner diameter of the bowl will be [SCRA 1998] |
| A. | 0.94 m |
| B. | 0.97 m |
| C. | 0.98 m |
| D. | 0.99 m |
| Answer» D. 0.99 m | |
| 4222. |
Construction of submarines is based on [Kerala PMT 2005] |
| A. | Archimedes? principle |
| B. | Bernoulli?s theorem |
| C. | Pascal?s law |
| D. | Newton?s laws |
| Answer» B. Bernoulli?s theorem | |
| 4223. |
A large ship can float but a steel needle sinks because of [AFMC 2005] |
| A. | Viscosity |
| B. | Surface tension |
| C. | Density |
| D. | None of these |
| Answer» E. | |
| 4224. |
An ice block contains a glass ball when the ice melts within the water containing vessel, the level of water [AFMC 2005] |
| A. | Rises |
| B. | Falls |
| C. | Unchanged |
| D. | First rises and then falls |
| Answer» C. Unchanged | |
| 4225. |
A wooden cylinder floats vertically in water with half of its length immersed. The density of wood is |
| A. | Equal of that of water |
| B. | Half the density of water |
| C. | Double the density of water |
| D. | The question is incomplete |
| Answer» C. Double the density of water | |
| 4226. |
A candle of diameter d is floating on a liquid in a cylindrical container of diameter D (D>>d) as shown in figure. If it is burning at the rate of 2cm/hour then the top of the candle will [AIIMS 2005] |
| A. | Remain at the same height |
| B. | Fall at the rate of 1 cm/hour |
| C. | Fall at the rate of 2 cm/hour |
| D. | Go up the rate of 1cm/hour |
| Answer» C. Fall at the rate of 2 cm/hour | |
| 4227. |
Two pieces of metal when immersed in a liquid have equal upthrust on them; then |
| A. | Both pieces must have equal weights |
| B. | Both pieces must have equal densities |
| C. | Both pieces must have equal volumes |
| D. | Both are floating to the same depth |
| Answer» D. Both are floating to the same depth | |
| 4228. |
A boat carrying steel balls is floating on the surface of water in a tank. If the balls are thrown into the tank one by one, how will it affect the level of water [J&K CET 2005] |
| A. | It will remain unchanged |
| B. | It will rise |
| C. | It will fall |
| D. | First it will first rise and then fall |
| Answer» D. First it will first rise and then fall | |
| 4229. |
A log of wood of mass 120 Kg floats in water. The weight that can be put on the raft to make it just sink, should be (density of wood = 600 Kg/m3) [CPMT 2004] |
| A. | 80 Kg |
| B. | 50 Kg |
| C. | 60 Kg |
| D. | 30 Kg |
| Answer» B. 50 Kg | |
| 4230. |
A ball whose density is 0.4 × 103 kg/m3 falls into water from a height of 9 cm . To what depth does the ball sink |
| A. | 9 cm |
| B. | 6 cm |
| C. | 4.5 cm |
| D. | 2.25 cm |
| Answer» C. 4.5 cm | |
| 4231. |
A rectangular block is 5 cm × 5 cm × 10cm in size. The block is floating in water with 5 cm side vertical. If it floats with 10 cm side vertical, what change will occur in the level of water? |
| A. | No change |
| B. | It will rise |
| C. | It will fall |
| D. | It may rise or fall depending on the density of block |
| Answer» B. It will rise | |
| 4232. |
A cork is submerged in water by a spring attached to the bottom of a bowl. When the bowl is kept in an elevator moving with acceleration downwards, the length of spring |
| A. | Increases |
| B. | Decreases |
| C. | Remains unchanged |
| D. | None of these |
| Answer» C. Remains unchanged | |
| 4233. |
A body is just floating on the surface of a liquid. The density of the body is same as that of the liquid. The body is slightly pushed down. What will happen to the body [AIIMS 1980] |
| A. | It will slowly come back to its earlier position |
| B. | It will remain submerged, where it is left |
| C. | It will sink |
| D. | It will come out violently |
| Answer» C. It will sink | |
| 4234. |
A block of steel of size 5 cm × 5 cm × 5 cm is weighed in water. If the relative density of steel is 7, its apparent weight is [AFMC 1997] |
| A. | 6 × 5 × 5 × 5 gf |
| B. | 4 × 4 × 4 × 7 gf |
| C. | 5 × 5 × 5 × 7 gf |
| D. | 4 × 4 × 4 × 6 gf |
| Answer» B. 4 × 4 × 4 × 7 gf | |
| 4235. |
Two solids A and B float in water. It is observed that A floats with half its volume immersed and B floats with 2/3 of its volume immersed. Compare the densities of A and B |
| A. | 4 : 3 |
| B. | 2 : 3 |
| C. | 3 : 4 |
| D. | 1 : 3 |
| Answer» D. 1 : 3 | |
| 4236. |
An ice berg of density 900 Kg/m3 is floating in water of density 1000 Kg/m3. The percentage of volume of ice-cube outside the water is [CPMT 2004] |
| A. | 20% |
| B. | 35% |
| C. | 10% |
| D. | 25% |
| Answer» D. 25% | |
| 4237. |
If the velocity of sound in air is 350 m/s. Then the fundamental frequency of an open organ pipe of length 50 cm, will be [CPMT 1997; MH CET 2001; Pb. PMT 2001] |
| A. | 350 Hz |
| B. | 175 Hz |
| C. | 900 Hz |
| D. | 750 Hz |
| Answer» B. 175 Hz | |
| 4238. |
An air column in a pipe, which is closed at one end, will be in resonance with a vibrating body of frequency 166 Hz, if the length of the air column is [UPSEAT 2001] |
| A. | 2.00 m |
| B. | 1.50 m |
| C. | 1.00 m |
| D. | 0.50 m |
| Answer» E. | |
| 4239. |
An open tube is in resonance with string (frequency of vibration of tube is n0). If tube is dipped in water so that 75% of length of tube is inside water, then the ratio of the frequency of tube to string now will be [J & K CET 2005] |
| A. | 1 |
| B. | 2 |
| C. | \[\frac{2}{3}\] |
| D. | \[\frac{3}{2}\] |
| Answer» C. \[\frac{2}{3}\] | |
| 4240. |
In a resonance pipe the first and second resonances are obtained at depths 22.7 cm and 70.2 cm respectively. What will be the end correction [J & K CET 2005] |
| A. | 1.05 cm |
| B. | 115.5 cm |
| C. | 92.5 cm |
| D. | 113.5 cm |
| Answer» B. 115.5 cm | |
| 4241. |
An organ pipe open at one end is vibrating in first overtone and is in resonance with another pipe open at both ends and vibrating in third harmonic. The ratio of length of two pipes is [DCE 2005] |
| A. | 1 : 2 |
| B. | 4 : 1 |
| C. | 8 : 3 |
| D. | 3 : 8 |
| Answer» B. 4 : 1 | |
| 4242. |
It is desired to increase the fundamental resonance frequency in a tube which is closed at one end. This can be achieved by [Roorkee 2000] |
| A. | Replacing the air in the tube by hydrogen gas |
| B. | Increasing the length of the tube |
| C. | Decreasing the length of the tube |
| D. | Opening the closed end of the tube |
| Answer» B. Increasing the length of the tube | |
| 4243. |
In one metre long open pipe what is the harmonic of resonance obtained with a tuning fork of frequency 480 Hz [J & K CET 2005] |
| A. | First |
| B. | Second |
| C. | Third |
| D. | Fourth |
| Answer» D. Fourth | |
| 4244. |
An organ pipe, open from both end produces 5 beats per second when vibrated with a source of frequency 200 Hz. The second harmonic of the same pipes produces 10 beats per second with a source of frequency 420 Hz. The frequency of source is [DCE 2005] |
| A. | 195 Hz |
| B. | 205 Hz |
| C. | 190 Hz |
| D. | 210 Hz |
| Answer» C. 190 Hz | |
| 4245. |
If in an experiment for determination of velocity of sound by resonance tube method using a tuning fork of 512 Hz, first resonance was observed at 30.7 cm and second was obtained at 63.2 cm, then maximum possible error in velocity of sound is (consider actual speed of sound in air is 332 m/s) [IIT-JEE (Screening) 2005 |
| A. | 204 cm/sec |
| B. | 110 cm/sec |
| C. | 58 cm/sec |
| D. | 80 cm/sec |
| Answer» E. | |
| 4246. |
In open organ pipe, if fundamental frequency is n then the other frequencies are [BCECE 2005] |
| A. | n, 2n, 3n, 4n |
| B. | n, 3n, 5n |
| C. | n, 2n, 4n, 8n |
| D. | None of these |
| Answer» B. n, 3n, 5n | |
| 4247. |
An open pipe of length 33 cm resonates with frequency of 100 Hz. If the speed of sound is 330 m/s, then this frequency is [RPMT 2002] |
| A. | Fundamental frequency of the pipe |
| B. | Third harmonic of the pipe |
| C. | Second harmonic of the pipe |
| D. | Fourth harmonic of the pipe |
| Answer» D. Fourth harmonic of the pipe | |
| 4248. |
A student determines the velocity of sound with the help of a closed organ pipe. If the observed length for fundamental frequency is 24.7 m, the length for third harmonic will be [RPET 2002] |
| A. | 74.1 cm |
| B. | 72.7 cm |
| C. | 75.4 cm |
| D. | 73.1 cm |
| Answer» B. 72.7 cm | |
| 4249. |
What is the base frequency if a pipe gives notes of frequencies 425, 255 and 595 and decide whether it is closed at one end or open at both ends [UPSEAT 2001] |
| A. | 17, closed |
| B. | 85, closed |
| C. | 17, open |
| D. | 85, open |
| Answer» C. 17, open | |
| 4250. |
An empty vessel is partially filled with water, then the frequency of vibration of air column in the vessel [KCET 2000] |
| A. | Remains same |
| B. | Decreases |
| C. | Increases |
| D. | First increases then decreases |
| Answer» D. First increases then decreases | |