50278 + Interview Questions in Physics

1.	A box B of mass M hangs from an ideal spring of force constant k. A small particle A also of mass M is stuck to the ceiling of the box and the system is in equilibrium. The particle gets detached from the ceiling and falls to strike the floor of the box. It takes time t for the particle to hit the floor after it gets detached from the ceiling. The particle on hitting the floor sticks to it and the system thereafter oscillates with a time period of T. Find the height H of the box if it is given that t=T6. Assume that the floor and ceiling of the box always remain horizontal.
Answer» A box $B$ of mass $M$ hangs from an ideal spring of force constant $k$ . A small particle $A$ also of mass $M$ is stuck to the ceiling of the box and the system is in equilibrium. The particle gets detached from the ceiling and falls to strike the floor of the box. It takes time $t$ for the particle to hit the floor after it gets detached from the ceiling. The particle on hitting the floor sticks to it and the system thereafter oscillates with a time period of $T$ . Find the height $H$ of the box if it is given that $t = \frac{T}{6}$ . Assume that the floor and ceiling of the box always remain horizontal.

Discussion

2.	8. A body of mass 10 kg moves with a velocity of 2m per sec along a circular path of radius 8m. The power produced by the body will be?
Answer» 8. A body of mass 10 kg moves with a velocity of 2m per sec along a circular path of radius 8m. The power produced by the body will be?

Discussion

3.	Given the following two transfer functions for a process and disturbance, find the feed forward gain Kff.Gp(s)=7e−4s5s+1;Gd(s)=4e−5s4s+1
Answer» Given the following two transfer functions for a process and disturbance, find the feed forward gain $K_{f f} .$ $G_{p} (s) = \frac{7 e^{- 4 s}}{5 s + 1}; G_{d} (s) = \frac{4 e^{- 5 s}}{4 s + 1}$

Discussion

4.	The speeds of a body executing shm are β and α when the displacement of body are α and β respectively Time period of oscillation of body is
Answer» The speeds of a body executing shm are β and α when the displacement of body are α and β respectively Time period of oscillation of body is

Discussion

5.	The figure shows part of a bigger circuit. At the moment, the capacity of the capacitor is 6μF and decreasing at the constant rate 0.5 μFs−1. The potential difference across the capacitor at this moment is changing as under [direction of current is shown in figure] dVdt=2Vs−1, d2Vdt2=12 Vs−2 ___ The current in the 4Ω resistor is decreasing at the rate of 1 μAs−1. What is the potential difference (in micro volts) across the inductor at this moment?
Answer» The figure shows part of a bigger circuit. At the moment, the capacity of the capacitor is $6 μ F$ and decreasing at the constant rate $0.5 μ F s^{- 1}$ . The potential difference across the capacitor at this moment is changing as under [direction of current is shown in figure] $\frac{d V}{d t} = 2 V s^{- 1}, \frac{d^{2} V}{d t^{2}} = \frac{1}{2} V s^{- 2}$ ___ The current in the $4 Ω$ resistor is decreasing at the rate of $1 μ A s^{- 1}$ . What is the potential difference (in micro volts) across the inductor at this moment?

Discussion

6.	the engine of a car moving at a speed of 36kmph is switched off when it moves on a road inclined at 30 degrees with the horizontal,f the coefficient of friction between the surface of road and the tyres is 1/\sqrt3 find the dis†an ce travelled by the car before coming to rest,take g=10m/s^{2.
Answer» the engine of a car moving at a speed of 36kmph is switched off when it moves on a road inclined at 30 degrees with the horizontal,f the coefficient of friction between the surface of road and the tyres is 1/\sqrt3 find the dis†an ce travelled by the car before coming to rest,take g=10m/s^{2.

Discussion

7.	If a block is protected up along an inclined plane with acceleration 'a', what will be the acceleration?
Answer» If a block is protected up along an inclined plane with acceleration 'a', what will be the acceleration?

Discussion

8.	Is it necessary for a transmitting antenna to be at the same heightas that of the receiving antenna for line-of-sight communication? ATV transmitting antenna is 81m tall. How much service area can it cover if the receiving antenna is at the ground level?
Answer» Is it necessary for a transmitting antenna to be at the same heightas that of the receiving antenna for line-of-sight communication? ATV transmitting antenna is 81m tall. How much service area can it cover if the receiving antenna is at the ground level?

Discussion

9.	the position of a particle along x axis at time t is given as x=1+t-t2. the distance travelled by the particle in first 2 seconds is 1. 1m 2. 2m 3. 2.5m 4. 3m
Answer» the position of a particle along x axis at time t is given as x=1+t-t2. the distance travelled by the particle in first 2 seconds is 1. 1m 2. 2m 3. 2.5m 4. 3m

9.

the position of a particle along x axis at time t is given as x=1+t-t2. the distance travelled by the particle in first 2 seconds is 1. 1m 2. 2m 3. 2.5m 4. 3m

Answer»

the position of a particle along x axis at time t is given as x=1+t-t2. the distance travelled by the particle in first 2 seconds is

1. 1m

2. 2m

3. 2.5m

4. 3m

Discussion

10.	In a gas turbine power plant if maximum temperature in the cycle is 1200K and the minimum temperature in the cycle is 300K. The isentropic efficiency of compressor and turbine is 0.8 each, then what will be the value of optimum pressure ratio (approximately) for maximum work output in the cycle?4.096
Answer» In a gas turbine power plant if maximum temperature in the cycle is 1200K and the minimum temperature in the cycle is 300K. The isentropic efficiency of compressor and turbine is 0.8 each, then what will be the value of optimum pressure ratio (approximately) for maximum work output in the cycle? 4.096

Discussion

11.	If x>0, y>0, x+y=3 and xy is maximum then the maximum value of xy is ? (a) 9/4 (b) 3/2 (c) 5/6 (d) 2/7
Answer» If x>0, y>0, x+y=3 and xy is maximum then the maximum value of xy is ? (a) 9/4 (b) 3/2 (c) 5/6 (d) 2/7

Discussion

12.	a body is thrown vertically upward with velocity 100 m/s^2 and it travels 5 m in last second of its upward journey . If same body is thrown upward with velocity 200m/s^2 , then the distance it travels in last second of its upward journey is .(take g=10m/s^2).
Answer» a body is thrown vertically upward with velocity 100 m/s^2 and it travels 5 m in last second of its upward journey . If same body is thrown upward with velocity 200m/s^2 , then the distance it travels in last second of its upward journey is .(take g=10m/s^2).

Discussion

13.	20. A particle start from rest and moves with a constant acceleration for 20 seconds if it covers s1 distance in 1st 10 second then s2 distance in next 10 seconds then correct relation between s1 and s2 is?
Answer» 20. A particle start from rest and moves with a constant acceleration for 20 seconds if it covers s1 distance in 1st 10 second then s2 distance in next 10 seconds then correct relation between s1 and s2 is?

Discussion

14.	Two Polaroids, A and B are kept with their transmission axes at an angle θ with respect to one another. If the transmitted intensity of light, It=0.125I0, where I0 is the intensity of light incident on the system, then find the value of θ.
Answer» Two Polaroids, $A$ and $B$ are kept with their transmission axes at an angle $θ$ with respect to one another. If the transmitted intensity of light, $I_{t} = 0.125 I_{0}$ , where $I_{0}$ is the intensity of light incident on the system, then find the value of $θ$ .

Discussion

15.	49. If a simple pendulum of length l and mass m has maximum angular displacement x , then find it's maximum kinetic energy .
Answer» 49. If a simple pendulum of length l and mass m has maximum angular displacement x , then find it's maximum kinetic energy .

Discussion

16.	How much distance, in metres, a wheel of 25 cm radius will cover, if it rotates 350 times?
Answer» How much distance, in metres, a wheel of 25 cm radius will cover, if it rotates 350 times?

Discussion

17.	If a carton containing a dozen crockery plates is dropped, then which of the following cannot be the ratio of broken and unbroken plates
Answer» If a carton containing a dozen crockery plates is dropped, then which of the following cannot be the ratio of broken and unbroken plates

Discussion

18.	Two waves y1 =Acos (0.5πx-100πt) and y2=Acos(0.46 πx-92πt) are travelling in a pipe placed along x-axis, where x is in metres and t is in seconds.Find the number of times intensity is maximum in time interval of 1 s, find wave velocity of louder sound and find the number of times y1+y2=0 at x=0 in 1 s
Answer» Two waves y1 =Acos (0.5πx-100πt) and y2=Acos(0.46 πx-92πt) are travelling in a pipe placed along x-axis, where x is in metres and t is in seconds. Find the number of times intensity is maximum in time interval of 1 s, find wave velocity of louder sound and find the number of times y1+y2=0 at x=0 in 1 s

Discussion

19.	A space vehicle of mass 300 kg is in circular orbit of radius 2Re about the earth. Energy required to shift vehicle from orbit of radius 2Re to orbit of radius 4Re is n×109 J. Here Re=6.4×106 is radius of earth and g=10 m/s2 then n is (Answer upto two digits after the decimal point.)
Answer» A space vehicle of mass 300 kg is in circular orbit of radius $2 R_{e}$ about the earth. Energy required to shift vehicle from orbit of radius $2 R_{e}$ to orbit of radius $4 R_{e}$ is $n \times 10^{9} J$ . Here $R_{e} = 6.4 \times 10^{6}$ is radius of earth and $g = 10 m / s^{2}$ then n is (Answer upto two digits after the decimal point.)

Discussion

20.	A non-conducting sheet of large surface area and thickness d contains uniform charge distribution of density ρ. Find the electric field at a point P inside the plane at a distance x from the central plane. Draw a qualitative graph of E against x for 0
Answer» A non-conducting sheet of large surface area and thickness d contains uniform charge distribution of density ρ. Find the electric field at a point P inside the plane at a distance x from the central plane. Draw a qualitative graph of E against x for 0

Discussion

21.	Find component of vector →A along the direction of →B A\|\|B and in perpendicular direction of →B A⊥B.
Answer» Find component of vector $\to A$ along the direction of $\to B$ A\|\|B and in perpendicular direction of $\to B$ $A ⊥ B$ .

21.

Find component of vector →A along the direction of →B A||B and in perpendicular direction of →B A⊥B.

Answer»

Find component of vector $\to A$ along the direction of $\to B$ A||B and in perpendicular direction of $\to B$ $A ⊥ B$ .

Discussion

22.	Two metallic spheres of radii r1 and r2 having charge q1 and q2 initially. if two spheres are connected by metallic wire then how charge distributes between two spheres.
Answer» Two metallic spheres of radii $r_{1}$ and $r_{2}$ having charge $q_{1}$ and $q_{2}$ initially. if two spheres are connected by metallic wire then how charge distributes between two spheres.

Discussion

23.	In a harbour, wind is blowing at the speed of 72 km/h and the flag on the mast of a boat anchored in the harbour flutters along the N-E direction. If the boat starts moving at a speed of 51 km/h to the north, what is the direction of the flag on the mast of the boat ?
Answer» In a harbour, wind is blowing at the speed of 72 km/h and the flag on the mast of a boat anchored in the harbour flutters along the N-E direction. If the boat starts moving at a speed of 51 km/h to the north, what is the direction of the flag on the mast of the boat ?

Discussion

24.	A fluorescent lamp of length 1m is placed horizontal at a depth of 1.2 m below a ceiling.a plane mirror of length 0.6 m is placed below the lamp parallel to and symmetric to the lamp at a distance of 2.4 m from it.the length of reflected path of the light on the celling is
Answer» A fluorescent lamp of length 1m is placed horizontal at a depth of 1.2 m below a ceiling.a plane mirror of length 0.6 m is placed below the lamp parallel to and symmetric to the lamp at a distance of 2.4 m from it.the length of reflected path of the light on the celling is

Discussion

25.	Ultravioletlight of wavelength 2271 Å from a 100 W mercury sourceirradiates a photo-cell made of molybdenum metal. If the stoppingpotential is −1.3 V, estimate the work function of the metal.How would the photo-cell respond to a high intensity (∼105W m−2)red light of wavelength 6328 Å produced by a He-Ne laser?
Answer» Ultraviolet light of wavelength 2271 Å from a 100 W mercury source irradiates a photo-cell made of molybdenum metal. If the stopping potential is −1.3 V, estimate the work function of the metal. How would the photo-cell respond to a high intensity (∼10⁵ W m⁻²) red light of wavelength 6328 Å produced by a He-Ne laser?

Discussion

26.	what is the range of time scale ?
Answer» what is the range of time scale ?

Discussion

27.	The storage battery of a car has an emf of 12 V. If the internal resistance of the battery is 0.4 Ω, what is the maximum current that can be drawn from the battery ?
Answer» The storage battery of a car has an emf of $12 V$ . If the internal resistance of the battery is $0.4 Ω$ , what is the maximum current that can be drawn from the battery ?

Discussion

28.	KE of a body is increased by 44%. What is the percent increase in momentum
Answer» KE of a body is increased by 44%. What is the percent increase in momentum

Discussion

29.	A 2 cm diameter coin rests flat on the bottom of a bowl in which the water is 20 cm deep (μw=4/3). 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 ( $μ_{w} = 4 / 3$ ). If the coin is viewed directly from above, what is its apparent diameter?

Discussion

30.	The graph between √Ek and 1P is (Ek = kinetic energy and P= linear momentum)
Answer» The graph between $\sqrt{E_{k}}$ and $\frac{1}{P}$ is $(E_{k}$ = kinetic energy and $P =$ linear momentum)

Discussion

31.	65.A 25 watt_220 volt bulb and a 100watt_220volt bulb are connected in parallel across a 440 volt line which bulb will fuse or no one fuse and why
Answer» 65.A 25 watt_220 volt bulb and a 100watt_220volt bulb are connected in parallel across a 440 volt line which bulb will fuse or no one fuse and why

Discussion

32.	Water is flowing in streamline motion in the tube as shown in the figure. Pressure in the tube is
Answer» Water is flowing in streamline motion in the tube as shown in the figure. Pressure in the tube is

32.

Water is flowing in streamline motion in the tube as shown in the figure. Pressure in the tube is

Answer»

Water is flowing in streamline motion in the tube as shown in the figure. Pressure in the tube is

Discussion

33.	The ceiling of a long hall is 25 m high. What is the maximum horizontal distance that a ball thrown with a speed of 40 m s ¯¹ can go without hitting the ceiling of the hall ?
Answer» The ceiling of a long hall is 25 m high. What is the maximum horizontal distance that a ball thrown with a speed of 40 m s ¯¹ can go without hitting the ceiling of the hall ?

Discussion

34.	Water flows through a vertical tube of variable cross section. The area of cross - section at A and B are 6 mm2 and 3 mm2 respectively. If 12 cm3 of water enters per second through A, find the pressure difference \|PA−PB\|. The separation between the cross-section at A and B is 100 cm. (Take density of water as 1000 kg/m3 and g=10 m/s2)
Answer» Water flows through a vertical tube of variable cross section. The area of cross - section at $A$ and $B$ are $6 {mm}^{2}$ and $3 {mm}^{2}$ respectively. If $12 {cm}^{3}$ of water enters per second through $A$ , find the pressure difference $\| P_{A} - P_{B} \|$ . The separation between the cross-section at $A$ and $B$ is $100 cm$ . (Take density of water as $1000 {kg/m}^{3}$ and $g = 10 {m/s}^{2}$ )

Discussion

35.	Draw a graph for a thin current carrying hollow conductor for variation of magnetic field with respect to distance R from its axis along the radius.
Answer» Draw a graph for a thin current carrying hollow conductor for variation of magnetic field with respect to distance $R$ from its axis along the radius.

Discussion

36.	A uniform rod of length L and mass M is pivoted freely at one end and placed in vertical position. What is the angular acceleration of the rod when it is at an angle θ with the vertical?
Answer» A uniform rod of length $L$ and mass $M$ is pivoted freely at one end and placed in vertical position. What is the angular acceleration of the rod when it is at an angle $θ$ with the vertical?

Discussion

37.	The deflection in a moving coil galvanometer is reduced to one third when it is shunted with a 20 ohm coil . The resistance of the galvanometer is?
Answer» The deflection in a moving coil galvanometer is reduced to one third when it is shunted with a 20 ohm coil . The resistance of the galvanometer is?

Discussion

38.	A rope of length L is vibrating in first overtone at both ends. Take two parts of small and equal length at positions l_1 =0.2L and l_2 = 0.45L from one end. if their maximum kinetic energy are K1 and k2 respectively then 1) k1=k2 2) k1>k2 3) k1
Answer» A rope of length L is vibrating in first overtone at both ends. Take two parts of small and equal length at positions l_1 =0.2L and l_2 = 0.45L from one end. if their maximum kinetic energy are K1 and k2 respectively then 1) k1=k2 2) k1>k2 3) k1

Discussion

39.	a bulb of resis†an ce 10 ohm conected to an inductor of induc†an ce L is in series with an ac marked 100V,50Hz. find capaci†an ce id current is in phase with voltage.
Answer» a bulb of resis†an ce 10 ohm conected to an inductor of induc†an ce L is in series with an ac marked 100V,50Hz. find capaci†an ce id current is in phase with voltage.

Discussion

40.	An AC circuit has R=100 Ω,C=2 μF and L=80 mH connected in series. The quality factor of the circuit is :
Answer» An $A C$ circuit has $R = 100 Ω, C = 2 μ F$ and $L = 80 mH$ connected in series. The quality factor of the circuit is :

Discussion

41.	A force is applied on a body of mass 20 kg moving with a velocity of 40 m/s. The body attains a velocity of 50 m/s in 2 seconds. Calculate the work done by the body.
Answer» A force is applied on a body of mass $20 kg$ moving with a velocity of $40 m/s$ . The body attains a velocity of $50 m/s$ in $2 seconds$ . Calculate the work done by the body.

Discussion

42.	what is diviation?
Answer» what is diviation?

Discussion

43.	A straight rod of negligible mass is mounted on a frictionless pivot and masses 2.5 kg and 1 kg are suspended at distances 40 cm and 100 cm respectively from the pivot as shown. The rod is held at an angle θ with the horizontal and released.
Answer» A straight rod of negligible mass is mounted on a frictionless pivot and masses 2.5 kg and 1 kg are suspended at distances 40 cm and 100 cm respectively from the pivot as shown. The rod is held at an angle $θ$ with the horizontal and released.

43.

A straight rod of negligible mass is mounted on a frictionless pivot and masses 2.5 kg and 1 kg are suspended at distances 40 cm and 100 cm respectively from the pivot as shown. The rod is held at an angle θ with the horizontal and released.

Answer»

A straight rod of negligible mass is mounted on a frictionless pivot and masses 2.5 kg and 1 kg are suspended at distances 40 cm and 100 cm respectively from the pivot as shown. The rod is held at an angle $θ$ with the horizontal and released.

Discussion

44.	The moment of inertia of HCl molecule about an axis passing through its centre of mass and perpendicular to the line joining the H+ and Cl− ions will be, if the interatomic distance is 1 oA
Answer» The moment of inertia of HCl molecule about an axis passing through its centre of mass and perpendicular to the line joining the $H^{+}$ and $C l^{-}$ ions will be, if the interatomic distance is 1 $o A$

Discussion

45.	139.Two point charges q and -q are at positions (0,0,d) and (0,0,-d) respectively.What is the electic field at (a,0,0)?
Answer» 139.Two point charges q and -q are at positions (0,0,d) and (0,0,-d) respectively.What is the electic field at (a,0,0)?

Discussion

46.	A ball is held at rest in position A by two light cords. The horizontal cord is now cut and the ball swings to position B. What is the ratio of the tension in the cord at position B to that at position A originally?
Answer» A ball is held at rest in position $A$ by two light cords. The horizontal cord is now cut and the ball swings to position $B$ . What is the ratio of the tension in the cord at position $B$ to that at position $A$ originally?

Discussion

47.	36. Volume of gas evolved when dilute H2SO4 is electrolysed using 2F at STP
Answer» 36. Volume of gas evolved when dilute H2SO4 is electrolysed using 2F at STP

Discussion

48.	Ram learned in high school that electric current is the flow of electrons. Ram’s teacher had also told him that at any temperature the electrons of any metal move very randomly with very high speeds (around 100km/second). So Ram imagines that when a current flows through a conductor, this random motion must cease and all electrons move in one particular direction like a marching army (flow in a sense)
Answer» Ram learned in high school that electric current is the flow of electrons. Ram’s teacher had also told him that at any temperature the electrons of any metal move very randomly with very high speeds (around 100km/second). So Ram imagines that when a current flows through a conductor, this random motion must cease and all electrons move in one particular direction like a marching army (flow in a sense)

Discussion

49.	A simple pendulum has time period T1 . The point of suspension is now moved upwards according to the relation y=kt2.(k=1 m/s2) where y is the vertical displacement. The time period now becomes T2 .The ratio of T21T22=x10. Find the value of x (g=10m/s2)
Answer» A simple pendulum has time period $T_{1}$ . The point of suspension is now moved upwards according to the relation $y = k t^{2} . (k = 1 m / s^{2})$ where $y$ is the vertical displacement. The time period now becomes $T_{2}$ .The ratio of $\frac{T_{1}^{2}}{T_{2}^{2}} = \frac{x}{10}$ . Find the value of x $(g = 10 m / s^{2})$

Discussion

50.	A particle moves from A to B along the semicircular curve as shown in the figure. The ratio of distance covered by particle to its displacement is
Answer» A particle moves from A to B along the semicircular curve as shown in the figure. The ratio of distance covered by particle to its displacement is

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

8. A body of mass 10 kg moves with a velocity of 2m per sec along a circular path of radius 8m. The power produced by the body will be?

Given the following two transfer functions for a process and disturbance, find the feed forward gain Kff.Gp(s)=7e−4s5s+1;Gd(s)=4e−5s4s+1

The speeds of a body executing shm are β and α when the displacement of body are α and β respectively Time period of oscillation of body is

the engine of a car moving at a speed of 36kmph is switched off when it moves on a road inclined at 30 degrees with the horizontal,f the coefficient of friction between the surface of road and the tyres is 1/\sqrt3 find the dis†an ce travelled by the car before coming to rest,take g=10m/s^{2.

If a block is protected up along an inclined plane with acceleration 'a', what will be the acceleration?

Is it necessary for a transmitting antenna to be at the same heightas that of the receiving antenna for line-of-sight communication? ATV transmitting antenna is 81m tall. How much service area can it cover if the receiving antenna is at the ground level?

the position of a particle along x axis at time t is given as x=1+t-t2. the distance travelled by the particle in first 2 seconds is 1. 1m 2. 2m 3. 2.5m 4. 3m

If x>0, y>0, x+y=3 and xy is maximum then the maximum value of xy is ? (a) 9/4 (b) 3/2 (c) 5/6 (d) 2/7

a body is thrown vertically upward with velocity 100 m/s^2 and it travels 5 m in last second of its upward journey . If same body is thrown upward with velocity 200m/s^2 , then the distance it travels in last second of its upward journey is .(take g=10m/s^2).

20. A particle start from rest and moves with a constant acceleration for 20 seconds if it covers s1 distance in 1st 10 second then s2 distance in next 10 seconds then correct relation between s1 and s2 is?

Two Polaroids, A and B are kept with their transmission axes at an angle θ with respect to one another. If the transmitted intensity of light, It=0.125I0,​ where I0​ is the intensity of light incident on the system, then find the value of θ.

49. If a simple pendulum of length l and mass m has maximum angular displacement x , then find it's maximum kinetic energy .

How much distance, in metres, a wheel of 25 cm radius will cover, if it rotates 350 times?

If a carton containing a dozen crockery plates is dropped, then which of the following cannot be the ratio of broken and unbroken plates

A space vehicle of mass 300 kg is in circular orbit of radius 2Re about the earth. Energy required to shift vehicle from orbit of radius 2Re to orbit of radius 4Re is n×109 J. Here Re=6.4×106 is radius of earth and g=10 m/s2 then n is (Answer upto two digits after the decimal point.)

A non-conducting sheet of large surface area and thickness d contains uniform charge distribution of density ρ. Find the electric field at a point P inside the plane at a distance x from the central plane. Draw a qualitative graph of E against x for 0

Find component of vector →A along the direction of →B A||B and in perpendicular direction of →B A⊥B.

Two metallic spheres of radii r1 and r2 having charge q1 and q2 initially. if two spheres are connected by metallic wire then how charge distributes between two spheres.

In a harbour, wind is blowing at the speed of 72 km/h and the flag on the mast of a boat anchored in the harbour flutters along the N-E direction. If the boat starts moving at a speed of 51 km/h to the north, what is the direction of the flag on the mast of the boat ?

A fluorescent lamp of length 1m is placed horizontal at a depth of 1.2 m below a ceiling.a plane mirror of length 0.6 m is placed below the lamp parallel to and symmetric to the lamp at a distance of 2.4 m from it.the length of reflected path of the light on the celling is

what is the range of time scale ?

The storage battery of a car has an emf of 12 V. If the internal resistance of the battery is 0.4 Ω, what is the maximum current that can be drawn from the battery ?

KE of a body is increased by 44%. What is the percent increase in momentum

A 2 cm diameter coin rests flat on the bottom of a bowl in which the water is 20 cm deep (μw=4/3). If the coin is viewed directly from above, what is its apparent diameter?

The graph between √Ek and 1P is (Ek = kinetic energy and P= linear momentum)

65.A 25 watt_220 volt bulb and a 100watt_220volt bulb are connected in parallel across a 440 volt line which bulb will fuse or no one fuse and why

Water is flowing in streamline motion in the tube as shown in the figure. Pressure in the tube is

The ceiling of a long hall is 25 m high. What is the maximum horizontal distance that a ball thrown with a speed of 40 m s ¯¹ can go without hitting the ceiling of the hall ?

Draw a graph for a thin current carrying hollow conductor for variation of magnetic field with respect to distance R from its axis along the radius.

A uniform rod of length L and mass M is pivoted freely at one end and placed in vertical position. What is the angular acceleration of the rod when it is at an angle θ with the vertical?

The deflection in a moving coil galvanometer is reduced to one third when it is shunted with a 20 ohm coil . The resistance of the galvanometer is?

A rope of length L is vibrating in first overtone at both ends. Take two parts of small and equal length at positions l_1 =0.2L and l_2 = 0.45L from one end. if their maximum kinetic energy are K1 and k2 respectively then 1) k1=k2 2) k1>k2 3) k1

a bulb of resis†an ce 10 ohm conected to an inductor of induc†an ce L is in series with an ac marked 100V,50Hz. find capaci†an ce id current is in phase with voltage.

An AC circuit has R=100 Ω,C=2 μF and L=80 mH connected in series. The quality factor of the circuit is :

A force is applied on a body of mass 20 kg moving with a velocity of 40 m/s. The body attains a velocity of 50 m/s in 2 seconds. Calculate the work done by the body.

what is diviation?

A straight rod of negligible mass is mounted on a frictionless pivot and masses 2.5 kg and 1 kg are suspended at distances 40 cm and 100 cm respectively from the pivot as shown. The rod is held at an angle θ with the horizontal and released.

The moment of inertia of HCl molecule about an axis passing through its centre of mass and perpendicular to the line joining the H+ and Cl− ions will be, if the interatomic distance is 1 oA

139.Two point charges q and -q are at positions (0,0,d) and (0,0,-d) respectively.What is the electic field at (a,0,0)?

A ball is held at rest in position A by two light cords. The horizontal cord is now cut and the ball swings to position B. What is the ratio of the tension in the cord at position B to that at position A originally?

36. Volume of gas evolved when dilute H2SO4 is electrolysed using 2F at STP

A simple pendulum has time period T1 . The point of suspension is now moved upwards according to the relation y=kt2.(k=1 m/s2) where y is the vertical displacement. The time period now becomes T2 .The ratio of T21T22=x10. Find the value of x (g=10m/s2)

A particle moves from A to B along the semicircular curve as shown in the figure. The ratio of distance covered by particle to its displacement is

Two Polaroids, A and B are kept with their transmission axes at an angle θ with respect to one another. If the transmitted intensity of light, It=0.125I0, where I0 is the intensity of light incident on the system, then find the value of θ.