This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
A steel wire with cross-section 3 cm2 has elastic limit 2.4×108 Pa . The maximum upwards acceleration that can be given to a 1200 kg elevator supported by this cable, if the stress is not exceeding one-third of elastic limit, is 2n. Then the value of n is [Answer upto two decimal points] [ Take g=10 m/s2] |
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Answer» A steel wire with cross-section 3 cm2 has elastic limit 2.4×108 Pa . The maximum upwards acceleration that can be given to a 1200 kg elevator supported by this cable, if the stress is not exceeding one-third of elastic limit, is 2n. Then the value of n is [Answer upto two decimal points] [ Take g=10 m/s2] |
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| 2. |
If the radius of a sphere is measure as 7m with an error of 0.02 m, then find the approximate error in calculating its volume. |
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Answer» If the radius of a sphere is measure as 7m with an error of 0.02 m, then find the approximate error in calculating its volume. |
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| 3. |
The acceleration of the particle moving in positive x− direction with an initial velocity of 20 m/s is 4 m/s2. Its velocity at t=5 sec is |
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Answer» The acceleration of the particle moving in positive x− direction with an initial velocity of 20 m/s is 4 m/s2. Its velocity at t=5 sec is |
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| 4. |
In the arrangement shown in figure, the relation between acceleration of blocks m1 and m2 is |
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Answer» In the arrangement shown in figure, the relation between acceleration of blocks m1 and m2 is |
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| 5. |
A soap bubble is blown with the help of a mechanical pump at the mouth of a tube. The pump produces constant increase in the radius per minute of the bubble, irrespective of its internal pressure. The graph between the excess pressure p inside the soap bubble and time t will be |
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Answer» A soap bubble is blown with the help of a mechanical pump at the mouth of a tube. The pump produces constant increase in the radius per minute of the bubble, irrespective of its internal pressure. The graph between the excess pressure p inside the soap bubble and time t will be |
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| 6. |
What is Angular Displacement? |
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Answer» What is Angular Displacement? |
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| 7. |
The rubbed insulators able to retain charges placed on them so they were called dielectrics and rub conductors could not retain charges placed on them but immediately drained away the charges so they were called non electric I want to know the reason for this please explain me |
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Answer» The rubbed insulators able to retain charges placed on them so they were called dielectrics and rub conductors could not retain charges placed on them but immediately drained away the charges so they were called non electric I want to know the reason for this please explain me |
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| 8. |
An electron has kinectic energy 2.8*10^-23 j find de Broglie wavelength is |
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Answer» An electron has kinectic energy 2.8*10^-23 j find de Broglie wavelength is |
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| 9. |
The mass of an oxygen molecule is about 16 times that of a hydrogen molecule. At room Temperature the rms speed of oxygen molecules is v. The rms speed of the hydrogen molecules at the same temperature will be |
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Answer» The mass of an oxygen molecule is about 16 times that of a hydrogen molecule. At room Temperature the rms speed of oxygen molecules is v. The rms speed of the hydrogen molecules at the same temperature will be |
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| 10. |
A heavy uniform rod is hanging vertically from a fixed support. It is stretched by its own weight. The diameter of the rod is |
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Answer» A heavy uniform rod is hanging vertically from a fixed support. It is stretched by its own weight. The diameter of the rod is |
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| 11. |
What is the velocity of projectile when it mooves perpendicular to initial velocity? |
| Answer» What is the velocity of projectile when it mooves perpendicular to initial velocity? | |
| 12. |
A stone is dropped from the top of a cliff and is found to travel 44.1m in the last second before it reaches the ground. Find the height of the cliff. (Can we use 1:3:5 method if yes then how) |
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Answer» A stone is dropped from the top of a cliff and is found to travel 44.1m in the last second before it reaches the ground. Find the height of the cliff. (Can we use 1:3:5 method if yes then how) |
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| 13. |
Two particles A and B are thrown vertically upward with velocity, 5 m/s and 10 m/s respectively (g=10m/s2). Find separation between them after one second. (Use relative motion approach) |
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Answer» Two particles A and B are thrown vertically upward with velocity, 5 m/s and 10 m/s respectively (g=10m/s2). Find separation between them after one second. (Use relative motion approach)
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| 14. |
A ball at rest is projected horizontally from a table in front of a vertical plane mirror as shown in the figure. At any time t, the velocity of image with respect to ground can be written as : |
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Answer» A ball at rest is projected horizontally from a table in front of a vertical plane mirror as shown in the figure. At any time t, the velocity of image with respect to ground can be written as : |
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| 15. |
A current of (2.5±0.05) A flows through a wire and develops a potential difference of (10±0.1) volt. Resistance of the wire in ohm, is |
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Answer» A current of (2.5±0.05) A flows through a wire and develops a potential difference of (10±0.1) volt. Resistance of the wire in ohm, is |
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| 16. |
In a series grouping of N cells, current in the external circuit is I. Number of cells to be reversed in polarity such that current becomes I3 is |
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Answer» In a series grouping of N cells, current in the external circuit is I. Number of cells to be reversed in polarity such that current becomes I3 is |
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| 17. |
A ball of mass 10 kg and density 1 gm/cm3 is attached to the base of a container having a liquid of density 1.1 gm/cm3, with the help of a spring of spring constant 200 N/m as shown in the figure. If the container starts going up with an acceleration 2 m/s2 , the elongation in the spring (in cm, upto two decimals) is - |
Answer» A ball of mass 10 kg and density 1 gm/cm3 is attached to the base of a container having a liquid of density 1.1 gm/cm3, with the help of a spring of spring constant 200 N/m as shown in the figure. If the container starts going up with an acceleration 2 m/s2 , the elongation in the spring (in cm, upto two decimals) is -
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| 18. |
The container A contains ice at 0∘C. A conducting uniform rod PQ of length 4R is used to transfer heat to the ice in the container. The end P of the rod is maintained at 100∘C and the other end Q is kept inside the container A. The complete ice melts in 23 minutes. In another experiments, two conductors in the shape of quarter circles of radii 2R and R are welded to the conductor PQ at M and N respectively and their other ends are inserted inside the container A. All conductors are made of the same material and have the same cross sectional area. Once again, the end P is maintained at 100∘C and this time, the complete ice melts in t minutes. Find t. [Assume no heat loss from the curved surface of the rods and take π≃3.0] |
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Answer» The container A contains ice at 0∘C. A conducting uniform rod PQ of length 4R is used to transfer heat to the ice in the container. The end P of the rod is maintained at 100∘C and the other end Q is kept inside the container A. The complete ice melts in 23 minutes. In another experiments, two conductors in the shape of quarter circles of radii 2R and R are welded to the conductor PQ at M and N respectively and their other ends are inserted inside the container A. All conductors are made of the same material and have the same cross sectional area. Once again, the end P is maintained at 100∘C and this time, the complete ice melts in t minutes. Find t. |
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| 19. |
A long straight neutral conductor carries a current l. Assume that all the free electrons in the conductor move with the same velocity v. A is a stationary observer while B is moving same velocity v parallel to the conductor |
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Answer» A long straight neutral conductor carries a current l. Assume that all the free electrons in the conductor move with the same velocity v. A is a stationary observer while B is moving same velocity v parallel to the conductor |
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| 20. |
A hollow, neutral conducting sphere of inner radius R1 and outer radius R2 encloses a charge q inside it which is located at a distance d (<R1) from the centre of the spheres. The potential at the centre of the shell is |
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Answer» A hollow, neutral conducting sphere of inner radius R1 and outer radius R2 encloses a charge q inside it which is located at a distance d (<R1) from the centre of the spheres. The potential at the centre of the shell is |
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| 21. |
A uniform rod of mass 6 kg is lying on a smooth horizontal surface. Its two ends are pulled by strings as shown in figure. Force exerted by 40 cm part of the rod on 10 cm part of the rod is |
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Answer» A uniform rod of mass 6 kg is lying on a smooth horizontal surface. Its two ends are pulled by strings as shown in figure. Force exerted by 40 cm part of the rod on 10 cm part of the rod is |
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| 22. |
The mass per unit length of a rod of length 3 m is directly proportional to distance x from its one end. The centre of mass of the rod from that end will be at |
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Answer» The mass per unit length of a rod of length 3 m is directly proportional to distance x from its one end. The centre of mass of the rod from that end will be at |
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| 23. |
Determine the Ratio of root mean square of Helium to Argon gas at the same temperature (MHe=4U & MAr=40U) |
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Answer» Determine the Ratio of root mean square of Helium to Argon gas at the same temperature (MHe=4U & MAr=40U) |
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| 24. |
Two blocks of mass 4 kg and 2 kg are connected by a heavy string and placed on rough horizontal plane. The 2 kg block is pulled with a constant force F. The coefficient of friction between the blocks and the ground is 0.5. What is the value of F so that tension in the string is constant throughout during the motion of the blocks : (g=10 m/s2) |
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Answer» Two blocks of mass 4 kg and 2 kg are connected by a heavy string and placed on rough horizontal plane. The 2 kg block is pulled with a constant force F. The coefficient of friction between the blocks and the ground is 0.5. What is the value of F so that tension in the string is constant throughout during the motion of the blocks : (g=10 m/s2) |
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| 25. |
A rod of mass m and length 2l hangs by two identical light threads tied to its ends. An insect of mass 3m8 lands on the rod gently at a distance l3 from the centre of the rod as shown and sticks to it. As a result one of the thread breaks. The acceleration of the insect just after the thread breaks given that the insect remains at rest with respect to the rod. |
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Answer» A rod of mass m and length 2l hangs by two identical light threads tied to its ends. An insect of mass 3m8 lands on the rod gently at a distance l3 from the centre of the rod as shown and sticks to it. As a result one of the thread breaks. The acceleration of the insect just after the thread breaks given that the insect remains at rest with respect to the rod. |
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| 26. |
A beam of cathode rays after gaining kinetic energy once it passes throught a potential difference of V is subjected to crossed electric (E) and magnetic fields (B). The fields are adjusted such that the beam is not deflected. The specific charge of the cathode rays is given by |
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Answer» A beam of cathode rays after gaining kinetic energy once it passes throught a potential difference of V is subjected to crossed electric (E) and magnetic fields (B). The fields are adjusted such that the beam is not deflected. The specific charge of the cathode rays is given by |
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| 27. |
In the figure shown capacitors A and B of capacitance C each are in steady state. A dielectric slab of dielectric constant K = 2 and dimensions equal to the inner dimensions of the capacitor is inserted in the space between the plates of the capacitor B. Choose the correct option(s): |
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Answer» In the figure shown capacitors A and B of capacitance C each are in steady state. A dielectric slab of dielectric constant K = 2 and dimensions equal to the inner dimensions of the capacitor is inserted in the space between the plates of the capacitor B. Choose the correct option(s): |
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| 28. |
A boat crossing a river moves with a velocity v relative to still water. The river is flowing with a velocity v2 with respect to the bank. The angle with respect to the flow direction with which the boat should move to minimize the drift is: |
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Answer» A boat crossing a river moves with a velocity v relative to still water. The river is flowing with a velocity v2 with respect to the bank. The angle with respect to the flow direction with which the boat should move to minimize the drift is: |
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| 29. |
Find a positive value of m for which the coefficient of x2 in the expression (1+x)m is 6. |
| Answer» Find a positive value of m for which the coefficient of x2 in the expression (1+x)m is 6. | |
| 30. |
A plane is in a level flight at a constant speed and each of its two wings has an area of 50 m2. If the speed of air is 180 km/h over the lower wing surface and 252 km/h over the upper wing surface, the plane's mass is [Lift force on the wings = weight of plane] (Take density of air = 1 kg/m3 and g=10 m/s2) |
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Answer» A plane is in a level flight at a constant speed and each of its two wings has an area of 50 m2. If the speed of air is 180 km/h over the lower wing surface and 252 km/h over the upper wing surface, the plane's mass is [Lift force on the wings = weight of plane] |
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| 31. |
What is the effect of the temperature on capacitance of a parallel plate capacitor. |
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Answer» What is the effect of the temperature on capacitance of a parallel plate capacitor. |
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| 32. |
70 cal of heat is required to raise the temperature of 2 moles of an ideal gas at constant pressure from 30∘ C to 35∘ C. The amount of heat required to raise the temperature of the same gas through same range of temperature (30∘ C to 35∘ C) at constant volume is Given (γ=7/5) |
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Answer» 70 cal of heat is required to raise the temperature of 2 moles of an ideal gas at constant pressure from 30∘ C to 35∘ C. The amount of heat required to raise the temperature of the same gas through same range of temperature (30∘ C to 35∘ C) at constant volume is Given (γ=7/5) |
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| 33. |
A small ball is suspended from point O by a thread of length l. A nail is driven into the wall at a distance of l2 below O, at A. The ball is drawn aside so that the thread takes up a horizontal position at the level of point O and then released. If highest point to which it rises is xly. Find (y - x)___ 4 |
Answer» A small ball is suspended from point O by a thread of length l. A nail is driven into the wall at a distance of l2 below O, at A. The ball is drawn aside so that the thread takes up a horizontal position at the level of point O and then released. If highest point to which it rises is xly. Find (y - x)___![]()
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| 34. |
Plates of a parallel plate capacitor of capacitance 3μF are given charges 2μC and 4μC as shown in figure. Charge flown through battery (in μC) as switch S is closed is |
Answer» Plates of a parallel plate capacitor of capacitance 3μF are given charges 2μC and 4μC as shown in figure. Charge flown through battery (in μC) as switch S is closed is |
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| 35. |
Two steel balls of equal diameter are connected by a rigid bar of negligible weight as shown and are dropped in the horizontal position from height h above the heavy steel and brass base plates. If the coefficient of restitution between the ball and steel base is 0.6 and that between the other ball and the brass base is 0.4 . The angular velocity of the bar immediately after rebound is (Assume the two impacts are simultaneous). |
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Answer» Two steel balls of equal diameter are connected by a rigid bar of negligible weight as shown and are dropped in the horizontal position from height h above the heavy steel and brass base plates. If the coefficient of restitution between the ball and steel base is 0.6 and that between the other ball and the brass base is 0.4 . The angular velocity of the bar immediately after rebound is |
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| 36. |
An electric heater of resistance 8 Ω draws 15 A current from the service mains for 2 hours. Calculate the rate at which heat is developed in the heater. |
| Answer» An electric heater of resistance 8 Ω draws 15 A current from the service mains for 2 hours. Calculate the rate at which heat is developed in the heater. | |
| 37. |
Ratio of the weights of a 1 kg block of iron and 1 kg block of wood as measured by a spring balance is: Given: Density of iron =7800 kg/m3, density of wood =800 kg/m3 and density of air =1.293 kg/m3 |
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Answer» Ratio of the weights of a 1 kg block of iron and 1 kg block of wood as measured by a spring balance is: |
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| 38. |
If the force constant of the spring is 50 N/m. Find the mass of the block if it rests in the given situation. Take g=10m/s2 |
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Answer» If the force constant of the spring is 50 N/m. Find the mass of the block if it rests in the given situation. Take g=10m/s2 |
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| 39. |
Why is slapping a person electromagnetic force and not muscular force? |
| Answer» Why is slapping a person electromagnetic force and not muscular force? | |
| 40. |
A block is lying on a horizontal frictionless surface. One end of a uniform rope is fixed to the block which is pulled in the horizontal direction by applying a force F at the other end. If the mass of the rope is half the mass of the block, the tension in the middle of the rope will be |
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Answer» A block is lying on a horizontal frictionless surface. One end of a uniform rope is fixed to the block which is pulled in the horizontal direction by applying a force F at the other end. If the mass of the rope is half the mass of the block, the tension in the middle of the rope will be |
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| 41. |
A body is projected at 30∘ with velocity v1 from point A on the ground. At the same time another body is projected vertically upwards from B with velocity v2 from the ground. The point B lies vertically below the highest point of the trajectory of ball A. For both the bodies to collide, what should be the ratio of v1/v2 ? |
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Answer» A body is projected at 30∘ with velocity v1 from point A on the ground. At the same time another body is projected vertically upwards from B with velocity v2 from the ground. The point B lies vertically below the highest point of the trajectory of ball A. For both the bodies to collide, what should be the ratio of v1/v2 ? |
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| 42. |
Distance between successive compression and rarefaction is 1 m and velocity of sound is 360 ms−1. Find the frequency of sound wave. |
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Answer» Distance between successive compression and rarefaction is 1 m and velocity of sound is 360 ms−1. Find the frequency of sound wave. |
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| 43. |
What is the frequency range of signals that propagates best through ionosphere? |
| Answer» What is the frequency range of signals that propagates best through ionosphere? | |
| 44. |
If the speed of the particle is v=8t3−3t2+2 m/s, the distance of the particle as a function of time t is |
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Answer» If the speed of the particle is v=8t3−3t2+2 m/s, the distance of the particle as a function of time t is |
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| 45. |
Assume that the temperature remains essentially constant in the upper part of the atmosphere. Obtain an expression for the variation in pressure with height in the upper atmosphere. The mean molecular weight of air is M. Assume a variable PO for the pressure at a height h = 0, where h = 0 depends on the choice of origin (could very well be at the beginning of the stratosphere, for example). |
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Answer» Assume that the temperature remains essentially constant in the upper part of the atmosphere. Obtain an expression for the variation in pressure with height in the upper atmosphere. The mean molecular weight of air is M. Assume a variable PO for the pressure at a height h = 0, where h = 0 depends on the choice of origin (could very well be at the beginning of the stratosphere, for example). |
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| 46. |
Which one of the following is the correct difference between Rod Cells and Cone Cells of our retina? |
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Answer» Which one of the following is the correct difference between Rod Cells and Cone Cells of our retina?
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| 47. |
Classify the following as scalar and vector quantities: (i) Time period (ii) Distance (iii) Force (iv) Velocity (v) Work done |
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Answer» Classify the following as scalar and vector quantities: |
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| 48. |
Four point masses, each of mass m are present at the four corners of a square of side length equal to a. Axis of rotation is passing through through one particle as shown in the figure below. The moment of inertia about the axis of rotation is |
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Answer» Four point masses, each of mass m are present at the four corners of a square of side length equal to a. Axis of rotation is passing through through one particle as shown in the figure below. The moment of inertia about the axis of rotation is |
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| 49. |
Is Lyman series continuous or not.? |
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Answer» Is Lyman series continuous or not.? |
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| 50. |
The position x of a particle moving along x-axis varies with time t as x=Again(ωt) where A and ω are positive constants. The acceleration of a particle varies with its position (x) as |
| Answer» The position x of a particle moving along x-axis varies with time t as x=Again(ωt) where A and ω are positive constants. The acceleration of a particle varies with its position (x) as | |