50278 + Interview Questions in Physics

1.	Which of the following is/are a unit vector for all values of θ ?
Answer» Which of the following is/are a unit vector for all values of $θ ?$

Discussion

2.	A ray is incident on a sphere of refractive index √2 as shown in figure. Angle of refraction of the ray inside sphere is 30∘ and ray underdoes TIR as shown. If total deviation suffered by the ray is x×30∘, then find x.
Answer» A ray is incident on a sphere of refractive index $\sqrt{2}$ as shown in figure. Angle of refraction of the ray inside sphere is $30^{\circ}$ and ray underdoes TIR as shown. If total deviation suffered by the ray is $x \times 30^{\circ}$ , then find $x$ .

Discussion

3.	From a solid sphere of mass M and radius R, a spherical portion of radius R2 is removed, as shown in the figure. Taking gravitational potential V=0 at r=∞ , the potential at the centre of the cavity thus formed is(G= gravitational constant)
Answer» From a solid sphere of mass $M$ and radius $R$ , a spherical portion of radius $\frac{R}{2}$ is removed, as shown in the figure. Taking gravitational potential $V = 0$ at $r = \infty$ , the potential at the centre of the cavity thus formed is ( $G =$ gravitational constant)

Discussion

4.	What will be the electric field through a ring of radius r if ring is chargeless & a point charge q kept L distance apart from the ring
Answer» What will be the electric field through a ring of radius r if ring is chargeless & a point charge q kept L distance apart from the ring

Discussion

5.	A particle goes in a circle of radius 2.0 cm. A concave mirror of focal length 20 cm is placed with its principal axis passing through the centre of the circle and perpendicular to its plane. The distance between the pole of the mirror and the centre of the circle is 30 cm. Calculate the radius of the circle formed by the image.
Answer» A particle goes in a circle of radius 2.0 cm. A concave mirror of focal length 20 cm is placed with its principal axis passing through the centre of the circle and perpendicular to its plane. The distance between the pole of the mirror and the centre of the circle is 30 cm. Calculate the radius of the circle formed by the image.

Discussion

6.	Acceleration versus velocity graph of a particle moving in a straight line starting from rest is as shown in figure. The corresponding velocity-time graph would be:
Answer» Acceleration versus velocity graph of a particle moving in a straight line starting from rest is as shown in figure. The corresponding velocity-time graph would be:

Discussion

7.	A body of mass 2 kg moving with a velocity (^i+2^j−3^k) ms−1 collides with another body of mass 3 kg moving with a velocity (2^i+^j+^k) in ms−1. If they stick together, the velocity in ms−1 of the composite body is
Answer» A body of mass 2 kg moving with a velocity $(^i + 2^j - 3^k) m s^{- 1}$ collides with another body of mass 3 kg moving with a velocity $(2^i +^j +^k)$ in $m s^{- 1}$ . If they stick together, the velocity in $m s^{- 1}$ of the composite body is

Discussion

8.	A particle of mass 1 kg slides down a frictionless track (AOC) starting from rest at a point A (height 2 m). After reaching C, the particle continues to move freely in air as a projectile. When it reaches its highest point P(height 1 m) the kinetic energy of the particle (in J) is:(Figure drawn is schematic and not to scale; take g=10 m/s2)
Answer» A particle of mass 1 $k g$ slides down a frictionless track (AOC) starting from rest at a point A (height 2 $m$ ). After reaching C, the particle continues to move freely in air as a projectile. When it reaches its highest point P(height 1 $m$ ) the kinetic energy of the particle (in $J$ ) is:(Figure drawn is schematic and not to scale; take $g = 10 m / s^{2}$ )

Discussion

9.	3.An ideal gas is made to undergo a cycle depicted by the PV diagram alongside. The curved line from A to B is an adiabat. Then- (A) The efficiency of this cycle is given by unity as no heat is released during the cycle (B) Heat is absorbed in the upper part of the straight line path and released in the lower part (C) If T1 and T2 are the maximum and minimum temperatures reached during the cycle, then the efficiency is given by 1 T2/T1 (D) The cycle can only be carried out in the reverse of the direction shown in figure
Answer» 3.An ideal gas is made to undergo a cycle depicted by the PV diagram alongside. The curved line from A to B is an adiabat. Then- (A) The efficiency of this cycle is given by unity as no heat is released during the cycle (B) Heat is absorbed in the upper part of the straight line path and released in the lower part (C) If T1 and T2 are the maximum and minimum temperatures reached during the cycle, then the efficiency is given by 1 T2/T1 (D) The cycle can only be carried out in the reverse of the direction shown in figure

Discussion

10.	The length of a conical pendulum is l=2 m and its bob has a mass of m=0.2 kg. The string will break if the tension T exceeds 4 N and g=10 m/s2. Then the smallest angle the string can make with the horizontal is
Answer» The length of a conical pendulum is $l = 2 m$ and its bob has a mass of $m = 0.2 kg$ . The string will break if the tension $T$ exceeds $4 N$ and $g = 10 {m/s}^{2}$ . Then the smallest angle the string can make with the horizontal is

Discussion

11.	In Exercise 4.11 obtain the frequency of revolution of the electron inits circular orbit. Does the answer depend on the speed of the electron? Explain.
Answer» In Exercise 4.11 obtain the frequency of revolution of the electron inits circular orbit. Does the answer depend on the speed of the electron? Explain.

Discussion

12.	Hii. Why a ray goes to a rarer to denser or denser to rarer medium it bends why it does not go straight.
Answer» Hii. Why a ray goes to a rarer to denser or denser to rarer medium it bends why it does not go straight.

Discussion

13.	78.Two long straight wires each carrying a current of 5A are placed along the X and Y-axis respectively the current point along the positive direction of the axes find the magnetic field at the point (a)(1m,1m) (b)(-1m,1m) (c)-1m,-1m)
Answer» 78.Two long straight wires each carrying a current of 5A are placed along the X and Y-axis respectively the current point along the positive direction of the axes find the magnetic field at the point (a)(1m,1m) (b)(-1m,1m) (c)-1m,-1m)

Discussion

14.	Two plane mirrors are inclined to each other such that a ray of light incident on the first mirror (M1) and parallel to the second mirror (M2) is finally reflected from second mirror M2 parallel to the first mirror (M1). The angle between the two mirrors will be
Answer» Two plane mirrors are inclined to each other such that a ray of light incident on the first mirror $(M_{1})$ and parallel to the second mirror $(M_{2})$ is finally reflected from second mirror $M_{2}$ parallel to the first mirror $(M_{1})$ . The angle between the two mirrors will be

Discussion

15.	Air is pumped into an automobile tyre's tube up to a pressure of 200 kPa in the morning when the air temperature is 200∘C. During the day the temperature rises to 400∘C and the tube expands by 2%. Calculate the pressure of the air in the tube at this temperature
Answer» Air is pumped into an automobile tyre's tube up to a pressure of 200 kPa in the morning when the air temperature is 200 $^{\circ}$ C. During the day the temperature rises to 400 $^{\circ}$ C and the tube expands by 2%. Calculate the pressure of the air in the tube at this temperature

Discussion

16.	A small ball of mass m and charge +q tied with a string of length l, rotating in a vertical circle under gravity and a uniform horizontal electric field E as shown. The tension in the string will be minimum for
Answer» A small ball of mass $m$ and charge $+ q$ tied with a string of length $l$ , rotating in a vertical circle under gravity and a uniform horizontal electric field $E$ as shown. The tension in the string will be minimum for

Discussion

17.	Two wires are wrapped over a wooden cylinder to form two co-axial loops carrying current i1 and i2 in the opposite directons as shown in figure. If i2=8i1, then the value of x (see the figure) for which B=0 at the origin
Answer» Two wires are wrapped over a wooden cylinder to form two co-axial loops carrying current $i_{1}$ and $i_{2}$ in the opposite directons as shown in figure. If $i_{2} = 8 i_{1}$ , then the value of $x$ (see the figure) for which $B = 0$ at the origin

Discussion

18.	Power supplied to a particle of mass 2 kg varies with time as P=3t22 watt. Here t is in second. If velocity of particle at t=0 is v=0. The velocity of particle at time t=2 s will be
Answer» Power supplied to a particle of mass $2 kg$ varies with time as $P = \frac{3 t^{2}}{2}$ watt. Here $t$ is in second. If velocity of particle at $t = 0$ is $v = 0$ . The velocity of particle at time $t = 2$ s will be

Discussion

19.	equation of trajectory of projectilr is given by y=10x-4/7x^{2 }.the range of the projectile is,if g=10m/s^{
Answer» equation of trajectory of projectilr is given by y=10x-4/7x^{2 }.the range of the projectile is,if g=10m/s^{

Discussion

20.	1. "Find the time taken by the particle in going from x=0 to x=A/2 where is the amplitude." Why can't we use cosine component instead of sine component.
Answer» 1. "Find the time taken by the particle in going from x=0 to x=A/2 where is the amplitude." Why can't we use cosine component instead of sine component.

Discussion

21.	Three particles of mass m each are placed at the three corners of an equilateral triangle of side a. Find the work wihch should be done on this system to increase th esides of the triangle to 2a.
Answer» Three particles of mass m each are placed at the three corners of an equilateral triangle of side a. Find the work wihch should be done on this system to increase th esides of the triangle to 2a.

Discussion

22.	two bulbs with power and potential difference (60W,220V) and (100W,220V) are connected in series with a battery . which bulb will glow brighter and why
Answer» two bulbs with power and potential difference (60W,220V) and (100W,220V) are connected in series with a battery . which bulb will glow brighter and why

Discussion

23.	A semicircular disc is cut out from a square sheet of side 20 cm as shown in the figure. Consider the material to be of uniform density and the origin to be at point O. What is the distance of the centre of mass of the new shape from y− axis (in cm) ? (Answer upto two decimal places)
Answer» A semicircular disc is cut out from a square sheet of side $20 cm$ as shown in the figure. Consider the material to be of uniform density and the origin to be at point $O$ . What is the distance of the centre of mass of the new shape from $y -$ axis (in $cm$ ) ? (Answer upto two decimal places)

Discussion

24.	Two racing cars of masses m1 and m2 are moving in circles of radii r1 and r2 respectively. Their speeds are such that each makes a complete circle in the same time t. The ratio of the angular speeds of the first to the second car is
Answer» Two racing cars of masses $m_{1}$ and $m_{2}$ are moving in circles of radii $r_{1}$ and $r_{2}$ respectively. Their speeds are such that each makes a complete circle in the same time $t$ . The ratio of the angular speeds of the first to the second car is

Discussion

25.	a plate of thickness t made of a material of refractive index μ is placed in front of one of the slits in a double slit experiment (a) Find the change in th eoptical path due to introduction of th plate. (b) What should be the minimum thickness t which will make the intensity at the centre of the fringe pattern zero? WAvelength of the light used is λ Neglect any absorption of light in the plate.
Answer» a plate of thickness t made of a material of refractive index $μ$ is placed in front of one of the slits in a double slit experiment (a) Find the change in th eoptical path due to introduction of th plate. (b) What should be the minimum thickness t which will make the intensity at the centre of the fringe pattern zero? WAvelength of the light used is $λ$ Neglect any absorption of light in the plate.

Discussion

26.	May I know what is Motion
Answer» May I know what is Motion

Discussion

27.	10. From the top of the tower a stone is thrown up and reaches the ground in time t1.A second stone is thrown down with the same speed and reaches the ground in time t2.A third stone is released from rest and reaches the ground in time t3 then the relation between them is?
Answer» 10. From the top of the tower a stone is thrown up and reaches the ground in time t1.A second stone is thrown down with the same speed and reaches the ground in time t2.A third stone is released from rest and reaches the ground in time t3 then the relation between them is?

Discussion

28.	A boy starts from point A and reaches to point E as shown in figure. If he takes 3 minutes to travel between any two consecutive points, then which of the following distance-time graph best represents it?एक लड़का बिंदु A से गति करना प्रारम्भ करता है तथा चित्र में दर्शाए अनुसार बिंदु E पर पहुँचता है। यदि वह किन्हीं दो क्रमिक बिंदुओं के मध्य गति करने में 3 मिनट लेता है, तब निम्न में से कौनसा दूरी-समय आरेख इसे सबसे सही रूप से प्रदर्शित करता है?
Answer» A boy starts from point A and reaches to point E as shown in figure. If he takes 3 minutes to travel between any two consecutive points, then which of the following distance-time graph best represents it? एक लड़का बिंदु A से गति करना प्रारम्भ करता है तथा चित्र में दर्शाए अनुसार बिंदु E पर पहुँचता है। यदि वह किन्हीं दो क्रमिक बिंदुओं के मध्य गति करने में 3 मिनट लेता है, तब निम्न में से कौनसा दूरी-समय आरेख इसे सबसे सही रूप से प्रदर्शित करता है?

Discussion

29.	In the given diagram, with what force must the man pull the rope to hold the plank in position? (Mass of the man is 80 k; neglect the weight of the plank, rope and pulley; take g=10 m/s2)
Answer» In the given diagram, with what force must the man pull the rope to hold the plank in position? $($ Mass of the man is $80 k$ ; neglect the weight of the plank, rope and pulley; take $g = 10 {m / s}^{2})$

Discussion

30.	If the maximum velocity and accelaration of a particle executing SHM are equal in magnitude,the time period will be : A)1.57sec B)3.14sec C)6.28sec D)12.56sec
Answer» If the maximum velocity and accelaration of a particle executing SHM are equal in magnitude,the time period will be : A)1.57sec B)3.14sec C)6.28sec D)12.56sec

30.

If the maximum velocity and accelaration of a particle executing SHM are equal in magnitude,the time period will be : A)1.57sec B)3.14sec C)6.28sec D)12.56sec

Answer»

If the maximum velocity and accelaration of a particle executing SHM are equal in magnitude,the time period will be :

A)1.57sec B)3.14sec C)6.28sec D)12.56sec

Discussion

31.	15.A stick of mass m and length l is pivoted at one end and is displaced through an angle theta .the increase in potential energy is
Answer» 15.A stick of mass m and length l is pivoted at one end and is displaced through an angle theta .the increase in potential energy is

Discussion

32.	In YDSE experiment a glass plate of refractive index 1.5 is placed infront of one of the slits. Minimum thickness 't' of this glass plate so that intensity of light at position of central maxima [before glass plate] remains unchanged is
Answer» In YDSE experiment a glass plate of refractive index 1.5 is placed infront of one of the slits. Minimum thickness 't' of this glass plate so that intensity of light at position of central maxima [before glass plate] remains unchanged is

Discussion

33.	The phase difference between two points separated by 0.8 m in a wave of frequency 120 Hz is 0.5π. The wave velocity is
Answer» The phase difference between two points separated by $0.8 m$ in a wave of frequency $120 Hz$ is $0.5 π$ . The wave velocity is

Discussion

34.	What is the difference between potential and potential difference?
Answer» What is the difference between potential and potential difference?

Discussion

35.	Two particles are eecuting SHM of same amplitude and frequency along the same straight line path. They pass each other when going in opp. diretion each time thier displacement is 3/2times of thier amplitude. What is the phase difference between them
Answer» Two particles are eecuting SHM of same amplitude and frequency along the same straight line path. They pass each other when going in opp. diretion each time thier displacement is 3/2times of thier amplitude. What is the phase difference between them

Discussion

36.	A beam of light converges to a point P. A concave lens of focal length 16 cm is placed in the path of the convergent beam 12 cm from P. How far from the lens does the beam converge?
Answer» A beam of light converges to a point $P$ . A concave lens of focal length $16 c m$ is placed in the path of the convergent beam $12 c m$ from $P$ . How far from the lens does the beam converge?

Discussion

37.	why voltameter is connected in parallel with conductor , while an ammeter is connected in series with a conductor
Answer» why voltameter is connected in parallel with conductor , while an ammeter is connected in series with a conductor

Discussion

38.	A vernier callipers has 25 divisions on its vernier scale for every 35 divisions on its main scale. If 1 cm on the main scale is split into 12 units, the least count of the callipers will be
Answer» A vernier callipers has 25 divisions on its vernier scale for every 35 divisions on its main scale. If 1 cm on the main scale is split into 12 units, the least count of the callipers will be

Discussion

39.	A rectangular lamina of mass 6 kg is placed in such a way that the centre of rectangular lamina coincides with the origin(O) as shown in figure. If Ix and Iy are the moment of inertia of rectangular lamina about x - axis and y - axis respectively, then find the ratio IxIy.
Answer» A rectangular lamina of mass $6 kg$ is placed in such a way that the centre of rectangular lamina coincides with the origin( $O$ ) as shown in figure. If $I_{x}$ and $I_{y}$ are the moment of inertia of rectangular lamina about x - axis and y - axis respectively, then find the ratio $\frac{I_{x}}{I_{y}}$ .

Discussion

40.	A Pump supplies oil at 0.002m3/sec. to a 50 mm diameter double acting cylinder and a rod diameter is 20 mm. If the load is 6000 N bolts in extending and retracting stroke, the piston velocity during the extension and retraction stroke are
Answer» A Pump supplies oil at $0.002 m^{3} / s e c .$ to a 50 mm diameter double acting cylinder and a rod diameter is 20 mm. If the load is 6000 N bolts in extending and retracting stroke, the piston velocity during the extension and retraction stroke are

Discussion

41.	There is a horizontal film of soap solution on it a thread is placed in form of a loop. The film is pierced inside the loop and the thread becomes a circular loop of radius R. If the surface tension of the soap solution is T, then the tension in the loop will be
Answer» There is a horizontal film of soap solution on it a thread is placed in form of a loop. The film is pierced inside the loop and the thread becomes a circular loop of radius R. If the surface tension of the soap solution is T, then the tension in the loop will be

Discussion

42.	A thin ring of radius `a' has charge Q uniformly distrib uted along its circumference. The potential at a point at a dis†an ce r from centre along the axis of ring is
Answer» A thin ring of radius `a' has charge Q uniformly distrib uted along its circumference. The potential at a point at a dis†an ce r from centre along the axis of ring is

Discussion

43.	The frequency of a tuning fork is 384 Hz and velocity of sound in air is 352 ms−1. How far sound has travelled when fork completes 36 vibrations?
Answer» The frequency of a tuning fork is $384 Hz$ and velocity of sound in air is $352 {ms}^{- 1}$ . How far sound has travelled when fork completes 36 vibrations?

Discussion

44.	A spherical mirror forms an image of magnification m=±3. The object distance, if focal length of mirror is 24 cm, may be
Answer» A spherical mirror forms an image of magnification m=±3. The object distance, if focal length of mirror is 24 cm, may be

Discussion

45.	A dip needle in a plane perpendicular to magnetic meridian will remain
Answer» A dip needle in a plane perpendicular to magnetic meridian will remain

Discussion

46.	Under isothermal condition two soap bubbles of radii r1 and r2 coalesce to form a single bubble of radius r. The external pressure is P0. Find the surface tension of the soap in terms of the given parameters.
Answer» Under isothermal condition two soap bubbles of radii $r_{1} and r_{2}$ coalesce to form a single bubble of radius $r$ . The external pressure is $P_{0}$ . Find the surface tension of the soap in terms of the given parameters.

Discussion

47.	A proton and an α − particle enter the same magnetic field which is perpendicular to their velocity. If both particles have same kinetic energy, then the ratio of their radii of the circular path is
Answer» A proton and an $α -$ particle enter the same magnetic field which is perpendicular to their velocity. If both particles have same kinetic energy, then the ratio of their radii of the circular path is

Discussion

48.	A concave mirror and a convex mirror of focal lengths 10 cm and 15 cm are placed at a distance of 70 cm. An object AB of height 2 cm is placed at a distance of 30 cm from the concave mirror as shown in the figure. If at first, ray is incident on the concave mirror and then on the convex mirror.Find the size and position of the image,
Answer» A concave mirror and a convex mirror of focal lengths $10 cm$ and $15 cm$ are placed at a distance of $70 cm$ . An object $AB$ of height $2 cm$ is placed at a distance of $30 cm$ from the concave mirror as shown in the figure. If at first, ray is incident on the concave mirror and then on the convex mirror.Find the size and position of the image,

Discussion

49.	If ∫cos4xdx=Ax+Bsin2x+Csin4x+D, then {A,B,C} equals
Answer» If $\int {cos}^{4} x d x = A x + B sin 2 x + C sin 4 x + D$ , then ${A, B, C}$ equals

Discussion

50.	Figure13.8 shows plot of PV/Tversus Pfor1.00×10–3kg of oxygen gas at two different temperatures.(a) Whatdoes the dotted plot signify?(b) Whichis true: T1> T2or T1< T2?(c) Whatis the value of PV/Twhere thecurves meet on the y-axis?(d) If we obtained similarplots for 1.00 ×10–3kg of hydrogen, would we get the same value of PV/Tat thepoint where the curves meet on the y-axis?If not, what mass of hydrogen yields the same value of PV/T(for lowpressure high temperature region of the plot)? (Molecular mass of H2= 2.02u, of O2= 32.0 u, R= 8.31 Jmo1–1K–1.)
Answer» Figure 13.8 shows plot of PV/T versus Pfor 1.00×10^–3 kg of oxygen gas at two different temperatures. (a) What does the dotted plot signify? (b) Which is true: T₁> T₂ or T₁ < T₂? (c) What is the value of PV/T where the curves meet on the y-axis? (d) If we obtained similar plots for 1.00 ×10^–3 kg of hydrogen, would we get the same value of PV/T at the point where the curves meet on the y-axis? If not, what mass of hydrogen yields the same value of PV/T (for low pressure high temperature region of the plot)? (Molecular mass of H₂= 2.02 u, of O₂ = 32.0 u, R = 8.31 J mo1^–1 K^–1.)

50.

Figure13.8 shows plot of PV/Tversus Pfor1.00×10–3kg of oxygen gas at two different temperatures.(a) Whatdoes the dotted plot signify?(b) Whichis true: T1> T2or T1< T2?(c) Whatis the value of PV/Twhere thecurves meet on the y-axis?(d) If we obtained similarplots for 1.00 ×10–3kg of hydrogen, would we get the same value of PV/Tat thepoint where the curves meet on the y-axis?If not, what mass of hydrogen yields the same value of PV/T(for lowpressure high temperature region of the plot)? (Molecular mass of H2= 2.02u, of O2= 32.0 u, R= 8.31 Jmo1–1K–1.)

Answer»

Figure
13.8 shows plot of PV/T
versus Pfor
1.00×10^–3
kg of oxygen gas at two different temperatures.

(a) What
does the dotted plot signify?

(b) Which
is true: T₁> T₂
or T₁
< T₂?

(c) What
is the value of PV/T
where the
curves meet on the y-axis?

(d) If we obtained similar
plots for 1.00 ×10^–3
kg of hydrogen, would we get the same value of PV/T
at the
point where the curves meet on the y-axis?
If not, what mass of hydrogen yields the same value of PV/T
(for low
pressure high temperature region of the plot)? (Molecular mass of H₂= 2.02
u, of O₂
= 32.0 u, R
= 8.31 J
mo1^–1
K^–1.)

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Which of the following is/are a unit vector for all values of θ ?

A ray is incident on a sphere of refractive index √2 as shown in figure. Angle of refraction of the ray inside sphere is 30∘ and ray underdoes TIR as shown. If total deviation suffered by the ray is x×30∘, then find x.

From a solid sphere of mass M and radius R, a spherical portion of radius R2 is removed, as shown in the figure. Taking gravitational potential V=0 at r=∞ , the potential at the centre of the cavity thus formed is(G= gravitational constant)

What will be the electric field through a ring of radius r if ring is chargeless & a point charge q kept L distance apart from the ring

Acceleration versus velocity graph of a particle moving in a straight line starting from rest is as shown in figure. The corresponding velocity-time graph would be:

A body of mass 2 kg moving with a velocity (^i+2^j−3^k) ms−1 collides with another body of mass 3 kg moving with a velocity (2^i+^j+^k) in ms−1. If they stick together, the velocity in ms−1 of the composite body is

The length of a conical pendulum is l=2 m and its bob has a mass of m=0.2 kg. The string will break if the tension T exceeds 4 N and g=10 m/s2. Then the smallest angle the string can make with the horizontal is

In Exercise 4.11 obtain the frequency of revolution of the electron inits circular orbit. Does the answer depend on the speed of the electron? Explain.

Hii. Why a ray goes to a rarer to denser or denser to rarer medium it bends why it does not go straight.

78.Two long straight wires each carrying a current of 5A are placed along the X and Y-axis respectively the current point along the positive direction of the axes find the magnetic field at the point (a)(1m,1m) (b)(-1m,1m) (c)-1m,-1m)

Two plane mirrors are inclined to each other such that a ray of light incident on the first mirror (M1) and parallel to the second mirror (M2) is finally reflected from second mirror M2 parallel to the first mirror (M1). The angle between the two mirrors will be

Air is pumped into an automobile tyre's tube up to a pressure of 200 kPa in the morning when the air temperature is 200∘C. During the day the temperature rises to 400∘C and the tube expands by 2%. Calculate the pressure of the air in the tube at this temperature

A small ball of mass m and charge +q tied with a string of length l, rotating in a vertical circle under gravity and a uniform horizontal electric field E as shown. The tension in the string will be minimum for

Two wires are wrapped over a wooden cylinder to form two co-axial loops carrying current i1 and i2 in the opposite directons as shown in figure. If i2=8i1, then the value of x (see the figure) for which B=0 at the origin

Power supplied to a particle of mass 2 kg varies with time as P=3t22 watt. Here t is in second. If velocity of particle at t=0 is v=0. The velocity of particle at time t=2 s will be

equation of trajectory of projectilr is given by y=10x-4/7x^{2 }.the range of the projectile is,if g=10m/s^{

1. "Find the time taken by the particle in going from x=0 to x=A/2 where is the amplitude." Why can't we use cosine component instead of sine component.

Three particles of mass m each are placed at the three corners of an equilateral triangle of side a. Find the work wihch should be done on this system to increase th esides of the triangle to 2a.

two bulbs with power and potential difference (60W,220V) and (100W,220V) are connected in series with a battery . which bulb will glow brighter and why

A semicircular disc is cut out from a square sheet of side 20 cm as shown in the figure. Consider the material to be of uniform density and the origin to be at point O. What is the distance of the centre of mass of the new shape from y− axis (in cm) ? (Answer upto two decimal places)

Two racing cars of masses m1 and m2 are moving in circles of radii r1 and r2 respectively. Their speeds are such that each makes a complete circle in the same time t. The ratio of the angular speeds of the first to the second car is

May I know what is Motion

10. From the top of the tower a stone is thrown up and reaches the ground in time t1.A second stone is thrown down with the same speed and reaches the ground in time t2.A third stone is released from rest and reaches the ground in time t3 then the relation between them is?

In the given diagram, with what force must the man pull the rope to hold the plank in position? (Mass of the man is 80 k; neglect the weight of the plank, rope and pulley; take g=10 m/s2)

If the maximum velocity and accelaration of a particle executing SHM are equal in magnitude,the time period will be : A)1.57sec B)3.14sec C)6.28sec D)12.56sec

15.A stick of mass m and length l is pivoted at one end and is displaced through an angle theta .the increase in potential energy is

In YDSE experiment a glass plate of refractive index 1.5 is placed infront of one of the slits. Minimum thickness 't' of this glass plate so that intensity of light at position of central maxima [before glass plate] remains unchanged is

The phase difference between two points separated by 0.8 m in a wave of frequency 120 Hz is 0.5π. The wave velocity is

What is the difference between potential and potential difference?

Two particles are eecuting SHM of same amplitude and frequency along the same straight line path. They pass each other when going in opp. diretion each time thier displacement is 3/2times of thier amplitude. What is the phase difference between them

A beam of light converges to a point P. A concave lens of focal length 16 cm is placed in the path of the convergent beam 12 cm from P. How far from the lens does the beam converge?

why voltameter is connected in parallel with conductor , while an ammeter is connected in series with a conductor

A vernier callipers has 25 divisions on its vernier scale for every 35 divisions on its main scale. If 1 cm on the main scale is split into 12 units, the least count of the callipers will be

A rectangular lamina of mass 6 kg is placed in such a way that the centre of rectangular lamina coincides with the origin(O) as shown in figure. If Ix and Iy are the moment of inertia of rectangular lamina about x - axis and y - axis respectively, then find the ratio IxIy.

A Pump supplies oil at 0.002m3/sec. to a 50 mm diameter double acting cylinder and a rod diameter is 20 mm. If the load is 6000 N bolts in extending and retracting stroke, the piston velocity during the extension and retraction stroke are

There is a horizontal film of soap solution on it a thread is placed in form of a loop. The film is pierced inside the loop and the thread becomes a circular loop of radius R. If the surface tension of the soap solution is T, then the tension in the loop will be

A thin ring of radius `a' has charge Q uniformly distrib uted along its circumference. The potential at a point at a dis†an ce r from centre along the axis of ring is

The frequency of a tuning fork is 384 Hz and velocity of sound in air is 352 ms−1. How far sound has travelled when fork completes 36 vibrations?

A spherical mirror forms an image of magnification m=±3. The object distance, if focal length of mirror is 24 cm, may be

A dip needle in a plane perpendicular to magnetic meridian will remain

Under isothermal condition two soap bubbles of radii r1 and r2 coalesce to form a single bubble of radius r. The external pressure is P0. Find the surface tension of the soap in terms of the given parameters.

A proton and an α − particle enter the same magnetic field which is perpendicular to their velocity. If both particles have same kinetic energy, then the ratio of their radii of the circular path is

If ∫cos4xdx=Ax+Bsin2x+Csin4x+D, then {A,B,C} equals