50278 + Interview Questions in Physics

1.	In an electromagnetic wave in free space, the root mean square value of the electric field is Erms=6 Vm−1. The peak value of the magnetic field is
Answer» In an electromagnetic wave in free space, the root mean square value of the electric field is $E_{r m s} = 6 V m^{- 1}$ . The peak value of the magnetic field is

Discussion

2.	A particle of mass 3 kg moving with a velocity of 6^i m/s collides head on with another particle of mass 5 kg moving with a velocity of −2^i m/s. If after the collision, first particle has a speed of 1 m/s along the negative X axis, find the coefficient of restitution.
Answer» A particle of mass $3 kg$ moving with a velocity of $6^i m/s$ collides head on with another particle of mass $5 kg$ moving with a velocity of $- 2^i m/s$ . If after the collision, first particle has a speed of $1 m/s$ along the negative $X$ axis, find the coefficient of restitution.

Discussion

3.	A block of mass m is at rest on a smooth inclined plane, which is rotated with a constant angular velocity ′ω′ about a vertical axis as shown in figure. Then, ω will be:
Answer» A block of mass $m$ is at rest on a smooth inclined plane, which is rotated with a constant angular velocity $^{'} ω^{'}$ about a vertical axis as shown in figure. Then, $ω$ will be:

Discussion

4.	A 2 cm diameter coin rests flat on the bottom of a bowl in which the water is 20 cm deep (μm=42). If the coin is viewed directly from above, what is its apparent diameter?
Answer» A 2 cm diameter coin rests flat on the bottom of a bowl in which the water is 20 cm deep $(μ_{m} = \frac{4}{2})$ . If the coin is viewed directly from above, what is its apparent diameter?

Discussion

5.	A bent tube is lowered into water stream as shown in the Fig. The velocity of the stream relative to the tube is equal to v=2m/s. The closed upper end of the tube located at height h0=10 cm above free surface of water has a small orifice. To what height h will the water get spurt?
Answer» A bent tube is lowered into water stream as shown in the Fig. The velocity of the stream relative to the tube is equal to $v = 2 m / s$ . The closed upper end of the tube located at height $h_{0} = 10 c m$ above free surface of water has a small orifice. To what height h will the water get spurt?

5.

A bent tube is lowered into water stream as shown in the Fig. The velocity of the stream relative to the tube is equal to v=2m/s. The closed upper end of the tube located at height h0=10 cm above free surface of water has a small orifice. To what height h will the water get spurt?

Answer»

A bent tube is lowered into water stream as shown in the Fig. The velocity of the stream relative to the tube is equal to $v = 2 m / s$ . The closed upper end of the tube located at height $h_{0} = 10 c m$ above free surface of water has a small orifice. To what height h will the water get spurt?

Discussion

6.	In physics What is the sign convention used for work done, in thermodynamics.
Answer» In physics What is the sign convention used for work done, in thermodynamics.

6.

In physics What is the sign convention used for work done, in thermodynamics.

Answer»

In physics What is the sign convention used for work done, in thermodynamics.

Discussion

7.	A piano wire A vibrates at a fundamental frequency of 600 Hz. A second identical wire B produces 6 beats per second with it when the tension in A is slightly increased. Find the ratio of the tension in A to the tension in B.
Answer» A piano wire A vibrates at a fundamental frequency of 600 Hz. A second identical wire B produces 6 beats per second with it when the tension in A is slightly increased. Find the ratio of the tension in A to the tension in B.

Discussion

8.	A particle moving with a velocity u is subjected to a retarding force as a result of which it decelerates at a rate a=-k√v where v is the instantaneous velocity and is the positive constant.Time taken by the particle to come to rest is given by
Answer» A particle moving with a velocity u is subjected to a retarding force as a result of which it decelerates at a rate a=-k√v where v is the instantaneous velocity and is the positive constant.Time taken by the particle to come to rest is given by

Discussion

9.	What is magnetic permeability?
Answer» What is magnetic permeability?

Discussion

10.	A projectile is fired with a speed u at an angle θ with the horizontal. Its speed when its direction of motion makes an angle α with the horizontal is
Answer» A projectile is fired with a speed $u$ at an angle $θ$ with the horizontal. Its speed when its direction of motion makes an angle $α$ with the horizontal is

Discussion

11.	If y=x2+5x32+2x, then dydx= ?
Answer» If $y = x^{2} + 5 x^{\frac{3}{2}} + \frac{2}{x}, t h e n \frac{d y}{d x} =$ ?

Discussion

12.	A particle is projected with a velocity u at two different angles which are complementary to each other. If H1 and H2 are the heights attained by them in each case, find the range of the particle.
Answer» A particle is projected with a velocity $u$ at two different angles which are complementary to each other. If $H_{1}$ and $H_{2}$ are the heights attained by them in each case, find the range of the particle.

Discussion

13.	A certain amount of a monoatomic ideal gas undergoes a process ρUη=C, whereρ is the density of the gas and U is the internal energy. It was found that the ratio r=ΔWΔQ for the process was r=2/3. What is the value of η?
Answer» A certain amount of a monoatomic ideal gas undergoes a process $ρ U^{η} = C$ , where $ρ$ is the density of the gas and $U$ is the internal energy. It was found that the ratio $r = \frac{Δ W}{Δ Q}$ for the process was $r = 2 / 3$ . What is the value of $η$ ?

Discussion

14.	Name the device used to measure liquid pressure?
Answer» Name the device used to measure liquid pressure?

Discussion

15.	A liquid of mass M and specific heat c is at temperature 2t. If another liquid of equal mass and thermal capacitiy 1.5 that of the first at a temperature of t3 is added to it, the resultant temperature will be
Answer» A liquid of mass $M$ and specific heat $c$ is at temperature $2 t$ . If another liquid of equal mass and thermal capacitiy $1.5$ that of the first at a temperature of $\frac{t}{3}$ is added to it, the resultant temperature will be

Discussion

16.	A container filled with air under pressure P0 contains a soap bubble of radius R. The air pressure has been reduced to half isothermally and the new radius of the bubble becomes 5R4. If the surface tension of the soap water solution is S, P0 is found to be nSR SI unit,where n is
Answer» A container filled with air under pressure $P_{0}$ contains a soap bubble of radius $R$ . The air pressure has been reduced to half isothermally and the new radius of the bubble becomes $\frac{5 R}{4}$ . If the surface tension of the soap water solution is $S$ , $P_{0}$ is found to be $\frac{n S}{R}$ SI unit,where $n$ is

Discussion

17.	For ΔABC. Choose incorrect option
Answer» For $Δ A B C$ . Choose incorrect option

Discussion

18.	A block of mass 4 kg is kept on a rough horizontal surface with coefficient of friction μs=0.4 and μk=0.3 and a time varying horizontal force F=4t applied on it, then the acceleration time graph of the particle is (g=10 m/s2)
Answer» A block of mass $4 k g$ is kept on a rough horizontal surface with coefficient of friction $μ_{s} = 0.4$ and $μ_{k} = 0.3$ and a time varying horizontal force $F = 4 t$ applied on it, then the acceleration time graph of the particle is $(g = 10 {m/s}^{2})$

Discussion

19.	Find derivative of f(x)=cosx1+sinx [Hint: sin2θ+cos2θ=1]
Answer» Find derivative of $f (x) = \frac{cos x}{1 + sin x}$ [Hint: ${sin}^{2} θ + {cos}^{2} θ = 1$ ]

Discussion

20.	The velocity distribution for the flow over a flat plate is given by u=2y−y2 in which u is the velocity in m/s at a distance y metres above the plate. Determine the shear stress at y=0.15 m. Take dynamic viscosity of the fluid as 8.5 poise.
Answer» The velocity distribution for the flow over a flat plate is given by $u = 2 y - y^{2}$ in which $u$ is the velocity in $m/s$ at a distance $y metres$ above the plate. Determine the shear stress at $y = 0.15 m$ . Take dynamic viscosity of the fluid as $8.5 poise$ .

Discussion

21.	A Carnot engine, having an efficiency of η=0.1 as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lowertemperature is :
Answer» A Carnot engine, having an efficiency of η=0.1 as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lowertemperature is :

Discussion

22.	Assume that the object is placed beyond C in a concave mirror. Why can't we take two raysnparallel to principal axis or one day parallel to principal axis and other along it or one along the principal axis and the other passing through C and why?
Answer» Assume that the object is placed beyond C in a concave mirror. Why can't we take two raysnparallel to principal axis or one day parallel to principal axis and other along it or one along the principal axis and the other passing through C and why?

Discussion

23.	A radioactive nucleus (initial mass number A and atomic number Z) emits 3α- particles and 2 positrons. The ratio of number of neutrons to that of protons in the final nucleus will be
Answer» A radioactive nucleus (initial mass number A and atomic number Z) emits 3 $α$ - particles and 2 positrons. The ratio of number of neutrons to that of protons in the final nucleus will be

Discussion

24.	Does the intensity of Maxima fringes keeps on decreasing while moving away from the centre or it remains constant? (Interference)
Answer» Does the intensity of Maxima fringes keeps on decreasing while moving away from the centre or it remains constant? (Interference)

Discussion

25.	A certain gas diffuses from two different vessels A and B. The vessel A has a circular orifice while vessel B has a square orifice of length equal to the radius of the orifice of vessel A. The ratio of the rates of diffusion of the gas from vessel A to vessel B assuming same temperature and pressure is:
Answer» A certain gas diffuses from two different vessels A and B. The vessel A has a circular orifice while vessel B has a square orifice of length equal to the radius of the orifice of vessel A. The ratio of the rates of diffusion of the gas from vessel A to vessel B assuming same temperature and pressure is:

Discussion

26.	The mean lives of a radioactive substance are 1620 and 405 years for α-emission and β-emission respectively. Find out the time during which three fourth of a sample will decay if it is decaying both by α-emission and β-emission simultaneously.
Answer» The mean lives of a radioactive substance are 1620 and 405 years for $α$ -emission and $β$ -emission respectively. Find out the time during which three fourth of a sample will decay if it is decaying both by $α$ -emission and $β$ -emission simultaneously.

Discussion

27.	Check the correctness of the equation wavelength = h/mv.
Answer» Check the correctness of the equation wavelength = h/mv.

Discussion

28.	If the speed of the particle is v=4t3−6t2+5 m/s, the distance of the particle as a function of time t is
Answer» If the speed of the particle is $v = 4 t^{3} - 6 t^{2} + 5 m/s$ , the distance of the particle as a function of time $t$ is

Discussion

29.	Let f:[0,∞)→R be a continuous function such that f(x)=1−2x+x∫0ex−tf(t) dt for all x∈[0,∞). Then the value of f(−5) is
Answer» Let $f : [0, \infty) \to R$ be a continuous function such that $f (x) = 1 - 2 x + x \int 0 e^{x - t} f (t) d t$ for all $x \in [0, \infty) .$ Then the value of $f (- 5)$ is

Discussion

30.	Three rectangular plate of dimension each (l×h) are arranged as shown in the figure. If the masses of plates (A,B,C) are in the ratio 1:2:1, then find the coordinates of the COM of the system.
Answer» Three rectangular plate of dimension each $(l \times h)$ are arranged as shown in the figure. If the masses of plates ( $A, B, C$ ) are in the ratio $1 : 2 : 1$ , then find the coordinates of the $COM$ of the system.

Discussion

31.	If I have two vectors of length 3 and 4. What are the maximum and minimum possible lengths of the resultant?
Answer» If I have two vectors of length 3 and 4. What are the maximum and minimum possible lengths of the resultant?

Discussion

32.	Consider the situation given in the diagram two cars are moving along road '1' and road '2'. Draw the direction of the motion of car 'B' as seen from car 'A'
Answer» Consider the situation given in the diagram two cars are moving along road '1' and road '2'. Draw the direction of the motion of car 'B' as seen from car 'A'

32.

Consider the situation given in the diagram two cars are moving along road '1' and road '2'. Draw the direction of the motion of car 'B' as seen from car 'A'

Answer»

Consider the situation given in the diagram two cars are moving along road '1' and road '2'. Draw the direction of the motion of car 'B' as seen from car 'A'

Discussion

33.	Two balls are thrown with the same speed but making complementary angle with the horizontal. If the angle of projection of one is 30∘ and its maximum height is h, then the maximum height of the other will be
Answer» Two balls are thrown with the same speed but making complementary angle with the horizontal. If the angle of projection of one is $30^{\circ}$ and its maximum height is $h$ , then the maximum height of the other will be

Discussion

34.	Find the least count of a screw gauge whose least count of linear scale is 1mm and the circular scale is divided in 50 divisions and 2 entire rotations makes to 1 division on linear scale.
Answer» Find the least count of a screw gauge whose least count of linear scale is 1mm and the circular scale is divided in 50 divisions and 2 entire rotations makes to 1 division on linear scale.

Discussion

35.	What Newton's law of cooling states?
Answer» What Newton's law of cooling states?

Discussion

36.	A solid sphere of radius R1 and volume charge density ρ=ρ0r is enclosed by a hollow sphere of radius R2 with negative surface charge density σ, such that the total charge in the system is zero. ρ0 is a positive constant and r is the distance from the centre of the sphere. The ratio R2R1 is
Answer» A solid sphere of radius $R_{1}$ and volume charge density $ρ = \frac{ρ_{0}}{r}$ is enclosed by a hollow sphere of radius $R_{2}$ with negative surface charge density $σ$ , such that the total charge in the system is zero. $ρ_{0}$ is a positive constant and r is the distance from the centre of the sphere. The ratio $\frac{R_{2}}{R_{1}}$ is

Discussion

37.	A baseball is thrown vertically into the air. The acceleration of the ball at its highest point is:
Answer» A baseball is thrown vertically into the air. The acceleration of the ball at its highest point is:

Discussion

38.	Find the weight of the air at 200C contained in a room with 4.0m×5.0m floor and a ceiling 3.0 m high. (Density of air at 200C is 1.20 kg/m3).
Answer» Find the weight of the air at 20⁰C contained in a room with $4.0 m \times 5.0 m$ floor and a ceiling 3.0 m high. (Density of air at 20⁰C is 1.20 kg/m³).

Discussion

39.	A mercury drop of radius 1 cm is sprayed into 106 droplets of equal size. The energy expended in this process is - (surface tension of mercury is equal to 32×10−2 N/m)
Answer» A mercury drop of radius $1 cm$ is sprayed into $10^{6}$ droplets of equal size. The energy expended in this process is - (surface tension of mercury is equal to $32 \times 10^{- 2} N/m$ )

39.

A mercury drop of radius 1 cm is sprayed into 106 droplets of equal size. The energy expended in this process is - (surface tension of mercury is equal to 32×10−2 N/m)

Answer»

A mercury drop of radius $1 cm$ is sprayed into $10^{6}$ droplets of equal size. The energy expended in this process is -

(surface tension of mercury is equal to $32 \times 10^{- 2} N/m$ )

Discussion

40.	A ball is projected horizontally with a speed v from the top of a plane inclined at an angle 45∘ with the horizontal. How far from the point of projection will the ball strike the plane?
Answer» A ball is projected horizontally with a speed $v$ from the top of a plane inclined at an angle $45^{\circ}$ with the horizontal. How far from the point of projection will the ball strike the plane?

Discussion

41.	Due to economic reasons, only the upper sideband of an AM wave is transmitted, but at the receiving station, there is a facility for generating the carrier. Show that if a device is available which can multiply two signals, then it is possible to recover the modulating signal at the receiver station.
Answer» Due to economic reasons, only the upper sideband of an AM wave is transmitted, but at the receiving station, there is a facility for generating the carrier. Show that if a device is available which can multiply two signals, then it is possible to recover the modulating signal at the receiver station.

Discussion

42.	A body is whirled in a horizontal circle of radius 20 cm. It has angular velocity of 10 rad/s. What is its linear velocity at any point on circular path
Answer» A body is whirled in a horizontal circle of radius 20 cm. It has angular velocity of 10 rad/s. What is its linear velocity at any point on circular path

Discussion

43.	The effect of pressure is observed in the case of ____.
Answer» The effect of pressure is observed in the case of ____.

Discussion

44.	Price elasticity of demand of a good is (-) 2. The consumer buys a certain quantity of this good at a price of Rs. 8 per unit. When the price falls, he buys 50% more quantity. What is the new price?
Answer» Price elasticity of demand of a good is (-) 2. The consumer buys a certain quantity of this good at a price of Rs. 8 per unit. When the price falls, he buys $50 %$ more quantity. What is the new price?

Discussion

45.	If A2−B2=x2−14 and AB=x2. Find the value of A6+B6.
Answer» If $A^{2} - B^{2} = x^{2} - \frac{1}{4} a n d A B = \frac{x}{2}$ . Find the value of $A^{6} + B^{6}$ .

Discussion

46.	Heat is supplied to a diatomic gas at a constant pressure. The ratio of ΔQ:ΔU:ΔW is
Answer» Heat is supplied to a diatomic gas at a constant pressure. The ratio of $Δ Q : Δ U : Δ W$ is

Discussion

47.	If y=lnx ,then dydx will be
Answer» If $y = ln x$ ,then $\frac{d y}{d x}$ will be

Discussion

48.	No/2 atoms of X(g) are converted into X+(g) by energy E1 . No/2 atoms of X(g) are converted into X-(g) by energy E2 . Hence the ionisation potential and electron affinity of X(g) per atom are: A. 2E1/No. , 2(E2-E1)/No B. 2E1/No. ,. 2E2/No C. E1-E2/No. ,. 2E2/No D. None is correct
Answer» N_o/2 atoms of X(g) are converted into X⁺(g) by energy E₁. N_o/2 atoms of X(g) are converted into X^-(g) by energy E₂. Hence the ionisation potential and electron affinity of X(g) per atom are: A. 2E₁/N_o., 2(E₂-E₁)/N_o B. 2E₁/N_o.,. 2E₂/N_o C. E₁-E₂/N_{o. ,.}2E₂/N_o D. None is correct

48.

No/2 atoms of X(g) are converted into X+(g) by energy E1 . No/2 atoms of X(g) are converted into X-(g) by energy E2 . Hence the ionisation potential and electron affinity of X(g) per atom are: A. 2E1/No. , 2(E2-E1)/No B. 2E1/No. ,. 2E2/No C. E1-E2/No. ,. 2E2/No D. None is correct

Answer»

N_o/2 atoms of X(g) are converted into X⁺(g) by energy E₁. N_o/2 atoms of X(g) are converted into X^-(g) by energy E₂. Hence the ionisation potential and electron affinity of X(g) per atom are:

A. 2E₁/N_o., 2(E₂-E₁)/N_o

B. 2E₁/N_o.,. 2E₂/N_o

C. E₁-E₂/N_{o. ,.}2E₂/N_o

D. None is correct

Discussion

49.	A train 300m length is going towards North at a speed of 30m/s. A Parrot flies at a speed of 10m/s towards south parallel to the railway track. Find the time taken by the Parrot to cross the train.
Answer» A train 300m length is going towards North at a speed of 30m/s. A Parrot flies at a speed of 10m/s towards south parallel to the railway track. Find the time taken by the Parrot to cross the train.

Discussion

50.	Two identical particles A and B, each of mass m, are interconnected by a spring of stiffness k. If particle B experiences a force F and the elongation of the spring is x, the acceleration of particle B relative to particle A is equal to
Answer» Two identical particles A and B, each of mass m, are interconnected by a spring of stiffness k. If particle B experiences a force F and the elongation of the spring is x, the acceleration of particle B relative to particle A is equal to

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

In an electromagnetic wave in free space, the root mean square value of the electric field is Erms=6 Vm−1. The peak value of the magnetic field is

A particle of mass 3 kg moving with a velocity of 6^i m/s collides head on with another particle of mass 5 kg moving with a velocity of −2^i m/s. If after the collision, first particle has a speed of 1 m/s along the negative X axis, find the coefficient of restitution.

A block of mass m is at rest on a smooth inclined plane, which is rotated with a constant angular velocity ′ω′ about a vertical axis as shown in figure. Then, ω will be:

A 2 cm diameter coin rests flat on the bottom of a bowl in which the water is 20 cm deep (μm=42). If the coin is viewed directly from above, what is its apparent diameter?

A bent tube is lowered into water stream as shown in the Fig. The velocity of the stream relative to the tube is equal to v=2m/s. The closed upper end of the tube located at height h0=10 cm above free surface of water has a small orifice. To what height h will the water get spurt?

In physics What is the sign convention used for work done, in thermodynamics.

A piano wire A vibrates at a fundamental frequency of 600 Hz. A second identical wire B produces 6 beats per second with it when the tension in A is slightly increased. Find the ratio of the tension in A to the tension in B.

A particle moving with a velocity u is subjected to a retarding force as a result of which it decelerates at a rate a=-k√v where v is the instantaneous velocity and is the positive constant.Time taken by the particle to come to rest is given by

What is magnetic permeability?

A projectile is fired with a speed u at an angle θ with the horizontal. Its speed when its direction of motion makes an angle α with the horizontal is

If y=x2+5x32+2x, then dydx= ?

A particle is projected with a velocity u at two different angles which are complementary to each other. If H1 and H2 are the heights attained by them in each case, find the range of the particle.

A certain amount of a monoatomic ideal gas undergoes a process ρUη=C, whereρ is the density of the gas and U is the internal energy. It was found that the ratio r=ΔWΔQ for the process was r=2/3. What is the value of η?

Name the device used to measure liquid pressure?

A liquid of mass M and specific heat c is at temperature 2t. If another liquid of equal mass and thermal capacitiy 1.5 that of the first at a temperature of t3 is added to it, the resultant temperature will be

A container filled with air under pressure P0 contains a soap bubble of radius R. The air pressure has been reduced to half isothermally and the new radius of the bubble becomes 5R4. If the surface tension of the soap water solution is S, P0 is found to be nSR SI unit,where n is

For ΔABC. Choose incorrect option

A block of mass 4 kg is kept on a rough horizontal surface with coefficient of friction μs=0.4 and μk=0.3 and a time varying horizontal force F=4t applied on it, then the acceleration time graph of the particle is (g=10 m/s2)

Find derivative of f(x)=cosx1+sinx [Hint: sin2θ+cos2θ=1]

The velocity distribution for the flow over a flat plate is given by u=2y−y2 in which u is the velocity in m/s at a distance y metres above the plate. Determine the shear stress at y=0.15 m. Take dynamic viscosity of the fluid as 8.5 poise.

A Carnot engine, having an efficiency of η=0.1 as heat engine, is used as a refrigerator. If the work done on the system is 10 J, the amount of energy absorbed from the reservoir at lowertemperature is :

Assume that the object is placed beyond C in a concave mirror. Why can't we take two raysnparallel to principal axis or one day parallel to principal axis and other along it or one along the principal axis and the other passing through C and why?

A radioactive nucleus (initial mass number A and atomic number Z) emits 3α- particles and 2 positrons. The ratio of number of neutrons to that of protons in the final nucleus will be

Does the intensity of Maxima fringes keeps on decreasing while moving away from the centre or it remains constant? (Interference)

The mean lives of a radioactive substance are 1620 and 405 years for α-emission and β-emission respectively. Find out the time during which three fourth of a sample will decay if it is decaying both by α-emission and β-emission simultaneously.

Check the correctness of the equation wavelength = h/mv.

If the speed of the particle is v=4t3−6t2+5 m/s, the distance of the particle as a function of time t is

Let f:[0,∞)→R be a continuous function such that f(x)=1−2x+x∫0ex−tf(t) dt for all x∈[0,∞). Then the value of f(−5) is

Three rectangular plate of dimension each (l×h) are arranged as shown in the figure. If the masses of plates (A,B,C) are in the ratio 1:2:1, then find the coordinates of the COM of the system.

If I have two vectors of length 3 and 4. What are the maximum and minimum possible lengths of the resultant?

Consider the situation given in the diagram two cars are moving along road '1' and road '2'. Draw the direction of the motion of car 'B' as seen from car 'A'

Two balls are thrown with the same speed but making complementary angle with the horizontal. If the angle of projection of one is 30∘ and its maximum height is h, then the maximum height of the other will be

Find the least count of a screw gauge whose least count of linear scale is 1mm and the circular scale is divided in 50 divisions and 2 entire rotations makes to 1 division on linear scale.

What Newton's law of cooling states?

A solid sphere of radius R1 and volume charge density ρ=ρ0r is enclosed by a hollow sphere of radius R2 with negative surface charge density σ, such that the total charge in the system is zero. ρ0 is a positive constant and r is the distance from the centre of the sphere. The ratio R2R1 is

A baseball is thrown vertically into the air. The acceleration of the ball at its highest point is:

Find the weight of the air at 200C contained in a room with 4.0m×5.0m floor and a ceiling 3.0 m high. (Density of air at 200C is 1.20 kg/m3).

A mercury drop of radius 1 cm is sprayed into 106 droplets of equal size. The energy expended in this process is - (surface tension of mercury is equal to 32×10−2 N/m)

A ball is projected horizontally with a speed v from the top of a plane inclined at an angle 45∘ with the horizontal. How far from the point of projection will the ball strike the plane?

A body is whirled in a horizontal circle of radius 20 cm. It has angular velocity of 10 rad/s. What is its linear velocity at any point on circular path

The effect of pressure is observed in the case of ____.

Price elasticity of demand of a good is (-) 2. The consumer buys a certain quantity of this good at a price of Rs. 8 per unit. When the price falls, he buys 50% more quantity. What is the new price?

If A2−B2=x2−14 and AB=x2. Find the value of A6+B6.

Heat is supplied to a diatomic gas at a constant pressure. The ratio of ΔQ:ΔU:ΔW is

If y=lnx ,then dydx will be

A train 300m length is going towards North at a speed of 30m/s. A Parrot flies at a speed of 10m/s towards south parallel to the railway track. Find the time taken by the Parrot to cross the train.

Two identical particles A and B, each of mass m, are interconnected by a spring of stiffness k. If particle B experiences a force F and the elongation of the spring is x, the acceleration of particle B relative to particle A is equal to