50278 + Interview Questions in Physics

1.	A LCR series combination is connected to an AC source. If voltages across the inductor, capacitor, resistor are 40 V, 80 V and 40 V respectively. Then the voltage across the AC source is x V.
Answer» A $LCR$ series combination is connected to an $AC$ source. If voltages across the inductor, capacitor, resistor are $40 V, 80 V$ and $40 V$ respectively. Then the voltage across the $AC$ source is $x V$ .

Discussion

2.	Which of the following molecule is optically active?
Answer» Which of the following molecule is optically active?

Discussion

3.	a body is moving in a circular path with a constant speed. state ,giving reason,whether (a) its momentum is constant or not, and (b) it has an acceleration or not.
Answer» a body is moving in a circular path with a constant speed. state ,giving reason,whether (a) its momentum is constant or not, and (b) it has an acceleration or not.

Discussion

4.	A particle moves from the point (2.0 ^i+4.0 ^j) m, at t=0, with an initial velocity (5.0 ^i+4.0 ^j) ms−1. It is acted upon by a constant force, which produces a constant acceleration of (4.0 ^i+4.0 ^j) ms−2. What is the distance of the particle, from the origin, at time 2s?
Answer» A particle moves from the point $(2.0^i + 4.0^j) m$ , at $t = 0$ , with an initial velocity $(5.0^i + 4.0^j) {ms}^{- 1}$ . It is acted upon by a constant force, which produces a constant acceleration of $(4.0^i + 4.0^j) {ms}^{- 2}$ . What is the distance of the particle, from the origin, at time $2 s$ ?

Discussion

5.	12.A triangular block of mass M rests on a smooth surface as shown in the figure. A cubical block of mass m rests on the inclined surface. If all surfaces are frictionless, the force that must be applied to M so as to keep m stationary relative to M is : (a) Mg tan 30^° (b) mg tan 30^° (c) (M+m)g tan 30^° (d) (M+m)g cos 30^°
Answer» 12.A triangular block of mass M rests on a smooth surface as shown in the figure. A cubical block of mass m rests on the inclined surface. If all surfaces are frictionless, the force that must be applied to M so as to keep m stationary relative to M is : (a) Mg tan 30^° (b) mg tan 30^° (c) (M+m)g tan 30^° (d) (M+m)g cos 30^°

Discussion

6.	63.A bullet of mass 10g traveling horizontally with a velocity of 150m/s strikes a stationary wooden block and comes to rest in 0.03s.calculate the distance of penetration of the bullet into the block. Also calculate the magnitude of the force exerted by the wooden block on the bullet
Answer» 63.A bullet of mass 10g traveling horizontally with a velocity of 150m/s strikes a stationary wooden block and comes to rest in 0.03s.calculate the distance of penetration of the bullet into the block. Also calculate the magnitude of the force exerted by the wooden block on the bullet

Discussion

7.	A man pulls a bucket of water from h metre deep well. If the mass of rope is m and mass of full water bucket is M then work done by men is
Answer» A man pulls a bucket of water from h metre deep well. If the mass of rope is m and mass of full water bucket is M then work done by men is

Discussion

8.	V is +ve or -ve in the case of concave mirror?
Answer» V is +ve or -ve in the case of concave mirror?

Discussion

9.	A convex surface (n=1.5) of radius 20 mm is immersed in water (n=1.33). Find image distance, if u=-80 mm.-185
Answer» A convex surface (n=1.5) of radius 20 mm is immersed in water (n=1.33). Find image distance, if u=-80 mm. -185

Discussion

10.	A mortar having muzzle velocity v0=215. m/s fires for maximum range across a level plain. Neglecting air resistance. The time of flight of the shell is ______sec.31
Answer» A mortar having muzzle velocity $v_{0} = 215.$ m/s fires for maximum range across a level plain. Neglecting air resistance. The time of flight of the shell is ______sec. 31

Discussion

11.	A stable LTI system characterized by the differential equation d2y(t)dt2+4dy(t)dt+3y(t)=dx(t)dt+2x(t)the value of h(0) is_______ where h(t) is the impulse response of the given system. 0.5
Answer» A stable LTI system characterized by the differential equation $\frac{d^{2} y (t)}{d t^{2}} + \frac{4 d y (t)}{d t} + 3 y (t) = \frac{d x (t)}{d t} + 2 x (t)$ the value of h(0) is_______ where h(t) is the impulse response of the given system. 0.5

Discussion

12.	Energy levels A, B and C of a certain atom correspond to increasing values of energy, i.e., EA<EB<EC. If λ1, λ2 and λ3 are the wavelengths of the radiation corresponding to transitions C to B, B to A and C to A respectively, which of the following relations is correct?
Answer» Energy levels A, B and C of a certain atom correspond to increasing values of energy, i.e., $E_{A} < E_{B} < E_{C}$ . If $λ_{1}$ , $λ_{2}$ and $λ_{3}$ are the wavelengths of the radiation corresponding to transitions C to B, B to A and C to A respectively, which of the following relations is correct?

Discussion

13.	From a disc of radius R and mass M, a circular hole of diameter R, whose rim passes through the center is cut. What is the moment of inertia of the remaining part of the disc about a perpendicular axis passing through the center?
Answer» From a disc of radius $R$ and mass $M$ , a circular hole of diameter $R$ , whose rim passes through the center is cut. What is the moment of inertia of the remaining part of the disc about a perpendicular axis passing through the center?

Discussion

14.	32.Two positive charges of magnitude q and 4q are situated at points (0,0) and (3,0) [ coordinates are in cm] the net electric field due to charge system at point (3cm , 4cm) is
Answer» 32.Two positive charges of magnitude q and 4q are situated at points (0,0) and (3,0) [ coordinates are in cm] the net electric field due to charge system at point (3cm , 4cm) is

Discussion

15.	A ball is projected with a velocity of 36 km/hr and it covers a range of 0.005 km. Find the angle at which it could have been projected.
Answer» A ball is projected with a velocity of 36 km/hr and it covers a range of 0.005 km. Find the angle at which it could have been projected.

Discussion

16.	A particle starts from the origin, goes along the x-axis to the point (20 m, o) and then returns along the same line to the point (-20 m, o). Find the distance and displacement of the particle during the trip.
Answer» A particle starts from the origin, goes along the x-axis to the point (20 m, o) and then returns along the same line to the point (-20 m, o). Find the distance and displacement of the particle during the trip.

Discussion

17.	The charge of one of two small charged sphere conductor is twice of the other. the two conductor repel each other with a force of 50dyn. if their distance is redued by 3cm the force becomes 50dyn. what is the magnitude of their charges and what was the initial distance?
Answer» The charge of one of two small charged sphere conductor is twice of the other. the two conductor repel each other with a force of 50dyn. if their distance is redued by 3cm the force becomes 50dyn. what is the magnitude of their charges and what was the initial distance?

Discussion

18.	A weakly damped harmonic oscillator of frequency n1 is driven by an external periodic force of frequency n2. When the steady state is reached, the frequency of the oscillator will be
Answer» A weakly damped harmonic oscillator of frequency $n_{1}$ is driven by an external periodic force of frequency $n_{2}$ . When the steady state is reached, the frequency of the oscillator will be

Discussion

19.	Electrons are bombarded to excite hydrogen atoms and six spectral lines are observed. If Eg is the ground state energy of hydrogen, the minimum energy the bombarding electrons should possess is
Answer» Electrons are bombarded to excite hydrogen atoms and six spectral lines are observed. If $E_{g}$ is the ground state energy of hydrogen, the minimum energy the bombarding electrons should possess is

Discussion

20.	An open organ pipe of length L vibrates in its fundamental mode. The pressure variation is maximum
Answer» An open organ pipe of length L vibrates in its fundamental mode. The pressure variation is maximum

Discussion

21.	Which of the following is realization of Z=AB+BC+CA?
Answer» Which of the following is realization of $Z = A B + B C + C A$ ?

Discussion

22.	What is the efficiency of a Carnot engine operating between higher temperature TH and lower temperature TL?
Answer» What is the efficiency of a Carnot engine operating between higher temperature $T_{H}$ and lower temperature $T_{L}$ ?

Discussion

23.	A projectile is given an initial velocity of (^i+2^j) m/s. The cartesian equation of its path is (g=10 m/s2)
Answer» A projectile is given an initial velocity of $(^i + 2^j) m/s$ . The cartesian equation of its path is $(g = 10 {m/s}^{2})$

Discussion

24.	30. Given 3(log 5-log3)-(log5-2log6)=2-log n find n
Answer» 30. Given 3(log 5-log3)-(log5-2log6)=2-log n find n

Discussion

25.	The coefficient of average rolling friction of a road is fr and its grade is +G%. If the grade of this road is doubled, what will be the percentage change in the braking distance (for the design vehicle to come to stop) measured along the horizontal (assume all other parameters are kept unchanged)?
Answer» The coefficient of average rolling friction of a road is $f_{r}$ and its grade is $+ G %$ . If the grade of this road is doubled, what will be the percentage change in the braking distance (for the design vehicle to come to stop) measured along the horizontal (assume all other parameters are kept unchanged)?

Discussion

26.	A force acts on a 10 g particle in such a way that the position of particle as a function of time is given by x=3+4t2, where x is in m and t is in seconds. The work done during first 7 seconds is
Answer» A force acts on a $10 g$ particle in such a way that the position of particle as a function of time is given by $x = 3 + 4 t^{2}$ , where $x$ is in $m$ and $t$ is in seconds. The work done during first $7$ seconds is

Discussion

27.	Orbit of a planet around a star is
Answer» Orbit of a planet around a star is

Discussion

28.	4.What is mass percentage and volume percent.
Answer» 4.What is mass percentage and volume percent.

Discussion

29.	66. The magnitude of the average electric field normally present in the atmosphere just above the surface of the earth is about 150 N/C ,directed inward towards the centre of the earth .This gives the total net surface charge carried by the earth to be ??
Answer» 66. The magnitude of the average electric field normally present in the atmosphere just above the surface of the earth is about 150 N/C ,directed inward towards the centre of the earth .This gives the total net surface charge carried by the earth to be ??

Discussion

30.	A rod is of length 2 m and of mass 1 kg. Moment of inertia about an axis perpendicular to its length and passing through one of its end is
Answer» A rod is of length 2 m and of mass 1 kg. Moment of inertia about an axis perpendicular to its length and passing through one of its end is

Discussion

31.	A stone ties to the end of a string 1m long is whirled in a horizontal circle with a constant speed. If the stone makes 22 revolution in 44 seconds, what is the magnitude and direction of acceleration of the stone
Answer» A stone ties to the end of a string 1m long is whirled in a horizontal circle with a constant speed. If the stone makes 22 revolution in 44 seconds, what is the magnitude and direction of acceleration of the stone

Discussion

32.	A block of mass M=5 kg is moving on a horizontal plane. An object of mass m=1 kg is dropped on to the block hitting it with a vertical velocity of v1=10 m/s. The speed of the block at the same instant is v2=2 m/s along the floor. The collision is momentary and the object sticks to the block upon collision. What will be the speed of the block just after the collision if the co-efficient of friction between the block and the horizontal plane is 0.4.
Answer» A block of mass $M = 5 kg$ is moving on a horizontal plane. An object of mass $m = 1 kg$ is dropped on to the block hitting it with a vertical velocity of $v_{1} = 10 m/s .$ The speed of the block at the same instant is $v_{2} = 2 m/s$ along the floor. The collision is momentary and the object sticks to the block upon collision. What will be the speed of the block just after the collision if the co-efficient of friction between the block and the horizontal plane is $0.4.$

Discussion

33.	How are the formulae of path of electron in electric and magnetic field derived? Please explain.
Answer» How are the formulae of path of electron in electric and magnetic field derived? Please explain.

Discussion

34.	What happen if any particle moves with the speed of light ? The mass of particle will increase or decrease ?
Answer» What happen if any particle moves with the speed of light ? The mass of particle will increase or decrease ?

Discussion

35.	116.Linear mass density of rod of length `l' is directly proportional to x^3, where `x' is distance from one end of rod. Centre of mass of rod lies at.
Answer» 116.Linear mass density of rod of length `l' is directly proportional to x^3, where `x' is distance from one end of rod. Centre of mass of rod lies at.

Discussion

36.	The work function for Ag metal is 7.5×10^{-19}J.Ag metal is beig exposed to light of frequency 1220\overset oA. Find the stopping potential and comment if light of wavelength 3600 Angstrom is used then willl the photoelectric effect would take place or not
Answer» The work function for Ag metal is 7.5×10^{-19}J.Ag metal is beig exposed to light of frequency 1220\overset oA. Find the stopping potential and comment if light of wavelength 3600 Angstrom is used then willl the photoelectric effect would take place or not

Discussion

37.	Question 12Can there be displacement of an object in the absence of any force acting on it? Think. Discuss this question with your friends and teacher.
Answer» Question 12 Can there be displacement of an object in the absence of any force acting on it? Think. Discuss this question with your friends and teacher.

Discussion

38.	A car is moving towards a fixed wall. It blows a horn of frequency 440 Hz. The frequency of reflected sound observed by the driver is 480 Hz. Then, find the speed of the car in km/hr. (Speed of sound in air is 350 m/s)
Answer» A car is moving towards a fixed wall. It blows a horn of frequency $440 Hz$ . The frequency of reflected sound observed by the driver is $480 Hz$ . Then, find the speed of the car in $km/hr$ . $($ Speed of sound in air is $350 m/s$ $)$

Discussion

39.	The time required for the light to pass through a glass slab (refractive index = 1.5) of thickness 4 mm is (c=3×108ms−1, speed of light in free space)
Answer» The time required for the light to pass through a glass slab (refractive index = 1.5) of thickness 4 mm is ( $c = 3 \times 10^{8} m s^{- 1}$ , speed of light in free space)

Discussion

40.	The field normal to the plane of wire of n turns and radius R which carries a current I measured on the axis at a small distance h from the centre of the coil. This is smaller than the field at the centre by the fraction (a)2h²/3R² (b)3R²/2h² (c)3h²/2R² (d)3h²/4R²
Answer» The field normal to the plane of wire of n turns and radius R which carries a current I measured on the axis at a small distance h from the centre of the coil. This is smaller than the field at the centre by the fraction (a)2h²/3R² (b)3R²/2h² (c)3h²/2R² (d)3h²/4R²

Discussion

41.	A surge of 15 kV magnitude travels along a cable towards its junction with an overhead line. The inductance and capacitance of the cable and overhead line are respectively 0.3 mH, 0.4 μF and 1.5 mH, 0.012 μF per km. The voltage rise at the junction due to the surge is _____ kV.27.84
Answer» A surge of 15 kV magnitude travels along a cable towards its junction with an overhead line. The inductance and capacitance of the cable and overhead line are respectively 0.3 mH, 0.4 $μ$ F and 1.5 mH, 0.012 $μ$ F per km. The voltage rise at the junction due to the surge is _____ kV. 27.84

Discussion

42.	Which of the following has more inertia:a) A rubber ball and a stone of the same size.b) A bicycle and a train.c) A five rupees coin and a one-rupee coin.
Answer» Which of the following has more inertia: a) A rubber ball and a stone of the same size. b) A bicycle and a train. c) A five rupees coin and a one-rupee coin.

Discussion

43.	Ball A is thrown vertically upward with a speed of 19.6 m/s from the top edge of a higgh building. as it passes the edge on the way down, a second ball B, is thrown downwards at 19.6m/s. which of the following is correct? (a) ball A hits the ground before ball B(b) the two balls hit the ground at same time(c)ball B hits the ground before ball A(d)not enough informtion is given
Answer» Ball A is thrown vertically upward with a speed of 19.6 m/s from the top edge of a higgh building. as it passes the edge on the way down, a second ball B, is thrown downwards at 19.6m/s. which of the following is correct? (a) ball A hits the ground before ball B (b) the two balls hit the ground at same time (c)ball B hits the ground before ball A (d)not enough informtion is given

Discussion

44.	In what way temperature at bottom of waterfall differs at temperature at top??
Answer» In what way temperature at bottom of waterfall differs at temperature at top??

Discussion

45.	14. what is the overall charge of NO molecule ?
Answer» 14. what is the overall charge of NO molecule ?

Discussion

46.	From what minimum height h must the system be released when spring is unstretched so that after perfectly inelastic collision (e = 0) with ground, B may be lifted off the ground (spring constant = k) from figure.
Answer» From what minimum height h must the system be released when spring is unstretched so that after perfectly inelastic collision (e = 0) with ground, B may be lifted off the ground (spring constant = k) from figure.

46.

From what minimum height h must the system be released when spring is unstretched so that after perfectly inelastic collision (e = 0) with ground, B may be lifted off the ground (spring constant = k) from figure.

Answer»

From what minimum height h must the system be released when spring is unstretched so that after perfectly inelastic collision (e = 0) with ground, B may be lifted off the ground (spring constant = k) from figure.

Discussion

47.	In an electromagnetic wave, the amplitude of electric field is 10 Vm−1. The frequency of the wave is 5×1014 Hz and the wave is propagating along z–axis, then total average energy density of E.M. wave is
Answer» In an electromagnetic wave, the amplitude of electric field is $10 {Vm}^{- 1}$ . The frequency of the wave is $5 \times 10^{14} Hz$ and the wave is propagating along $z -$ axis, then total average energy density of E.M. wave is

Discussion

48.	When a positively charged body is brought near a negatively charged microscope, why will the gold leaves first converge and then later diverge?
Answer» When a positively charged body is brought near a negatively charged microscope, why will the gold leaves first converge and then later diverge?

Discussion

49.	The spherical shape of rain-drop is due to
Answer» The spherical shape of rain-drop is due to

49.

The spherical shape of rain-drop is due to

Answer»

The spherical shape of rain-drop is due to

Discussion

50.	12. If Cosx+siny=underroot2 then Tanx is
Answer» 12. If Cosx+siny=underroot2 then Tanx is

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A LCR series combination is connected to an AC source. If voltages across the inductor, capacitor, resistor are 40 V, 80 V and 40 V respectively. Then the voltage across the AC source is x V.

Which of the following molecule is optically active?

a body is moving in a circular path with a constant speed. state ,giving reason,whether (a) its momentum is constant or not, and (b) it has an acceleration or not.

A particle moves from the point (2.0 ^i+4.0 ^j) m, at t=0, with an initial velocity (5.0 ^i+4.0 ^j) ms−1. It is acted upon by a constant force, which produces a constant acceleration of (4.0 ^i+4.0 ^j) ms−2. What is the distance of the particle, from the origin, at time 2s?

63.A bullet of mass 10g traveling horizontally with a velocity of 150m/s strikes a stationary wooden block and comes to rest in 0.03s.calculate the distance of penetration of the bullet into the block. Also calculate the magnitude of the force exerted by the wooden block on the bullet

A man pulls a bucket of water from h metre deep well. If the mass of rope is m and mass of full water bucket is M then work done by men is

V is +ve or -ve in the case of concave mirror?

A convex surface (n=1.5) of radius 20 mm is immersed in water (n=1.33). Find image distance, if u=-80 mm.-185

A mortar having muzzle velocity v0=215. m/s fires for maximum range across a level plain. Neglecting air resistance. The time of flight of the shell is ______sec.31

A stable LTI system characterized by the differential equation d2y(t)dt2+4dy(t)dt+3y(t)=dx(t)dt+2x(t)the value of h(0) is_______ where h(t) is the impulse response of the given system. 0.5

Energy levels A, B and C of a certain atom correspond to increasing values of energy, i.e., EA&lt;EB&lt;EC. If λ1, λ2 and λ3 are the wavelengths of the radiation corresponding to transitions C to B, B to A and C to A respectively, which of the following relations is correct?

From a disc of radius R and mass M, a circular hole of diameter R, whose rim passes through the center is cut. What is the moment of inertia of the remaining part of the disc about a perpendicular axis passing through the center?

32.Two positive charges of magnitude q and 4q are situated at points (0,0) and (3,0) [ coordinates are in cm] the net electric field due to charge system at point (3cm , 4cm) is

A ball is projected with a velocity of 36 km/hr and it covers a range of 0.005 km. Find the angle at which it could have been projected.

A particle starts from the origin, goes along the x-axis to the point (20 m, o) and then returns along the same line to the point (-20 m, o). Find the distance and displacement of the particle during the trip.

The charge of one of two small charged sphere conductor is twice of the other. the two conductor repel each other with a force of 50dyn. if their distance is redued by 3cm the force becomes 50dyn. what is the magnitude of their charges and what was the initial distance?

A weakly damped harmonic oscillator of frequency n1 is driven by an external periodic force of frequency n2. When the steady state is reached, the frequency of the oscillator will be

Electrons are bombarded to excite hydrogen atoms and six spectral lines are observed. If Eg is the ground state energy of hydrogen, the minimum energy the bombarding electrons should possess is

An open organ pipe of length L vibrates in its fundamental mode. The pressure variation is maximum

Which of the following is realization of Z=AB+BC+CA?

What is the efficiency of a Carnot engine operating between higher temperature TH and lower temperature TL?

A projectile is given an initial velocity of (^i+2^j) m/s. The cartesian equation of its path is (g=10 m/s2)

30. Given 3(log 5-log3)-(log5-2log6)=2-log n find n

The coefficient of average rolling friction of a road is fr and its grade is +G%. If the grade of this road is doubled, what will be the percentage change in the braking distance (for the design vehicle to come to stop) measured along the horizontal (assume all other parameters are kept unchanged)?

A force acts on a 10 g particle in such a way that the position of particle as a function of time is given by x=3+4t2, where x is in m and t is in seconds. The work done during first 7 seconds is

Orbit of a planet around a star is

4.What is mass percentage and volume percent.

66. The magnitude of the average electric field normally present in the atmosphere just above the surface of the earth is about 150 N/C ,directed inward towards the centre of the earth .This gives the total net surface charge carried by the earth to be ??

A rod is of length 2 m and of mass 1 kg. Moment of inertia about an axis perpendicular to its length and passing through one of its end is

A stone ties to the end of a string 1m long is whirled in a horizontal circle with a constant speed. If the stone makes 22 revolution in 44 seconds, what is the magnitude and direction of acceleration of the stone

How are the formulae of path of electron in electric and magnetic field derived? Please explain.

What happen if any particle moves with the speed of light ? The mass of particle will increase or decrease ?

116.Linear mass density of rod of length `l' is directly proportional to x^3, where `x' is distance from one end of rod. Centre of mass of rod lies at.

The work function for Ag metal is 7.5×10^{-19}J.Ag metal is beig exposed to light of frequency 1220\overset oA. Find the stopping potential and comment if light of wavelength 3600 Angstrom is used then willl the photoelectric effect would take place or not

Question 12Can there be displacement of an object in the absence of any force acting on it? Think. Discuss this question with your friends and teacher.

A car is moving towards a fixed wall. It blows a horn of frequency 440 Hz. The frequency of reflected sound observed by the driver is 480 Hz. Then, find the speed of the car in km/hr. (Speed of sound in air is 350 m/s)

The time required for the light to pass through a glass slab (refractive index = 1.5) of thickness 4 mm is (c=3×108ms−1, speed of light in free space)

The field normal to the plane of wire of n turns and radius R which carries a current I measured on the axis at a small distance h from the centre of the coil. This is smaller than the field at the centre by the fraction (a)2h²/3R² (b)3R²/2h² (c)3h²/2R² (d)3h²/4R²

A surge of 15 kV magnitude travels along a cable towards its junction with an overhead line. The inductance and capacitance of the cable and overhead line are respectively 0.3 mH, 0.4 μF and 1.5 mH, 0.012 μF per km. The voltage rise at the junction due to the surge is _____ kV.27.84

Which of the following has more inertia:a) A rubber ball and a stone of the same size.b) A bicycle and a train.c) A five rupees coin and a one-rupee coin.

In what way temperature at bottom of waterfall differs at temperature at top??

14. what is the overall charge of NO molecule ?

From what minimum height h must the system be released when spring is unstretched so that after perfectly inelastic collision (e = 0) with ground, B may be lifted off the ground (spring constant = k) from figure.

In an electromagnetic wave, the amplitude of electric field is 10 Vm−1. The frequency of the wave is 5×1014 Hz and the wave is propagating along z–axis, then total average energy density of E.M. wave is

When a positively charged body is brought near a negatively charged microscope, why will the gold leaves first converge and then later diverge?

The spherical shape of rain-drop is due to

12. If Cosx+siny=underroot2 then Tanx is

Energy levels A, B and C of a certain atom correspond to increasing values of energy, i.e., EA<EB<EC. If λ1, λ2 and λ3 are the wavelengths of the radiation corresponding to transitions C to B, B to A and C to A respectively, which of the following relations is correct?