50278 + Interview Questions in Physics

1.	A cube of wood supporting a mass of 200 g just floats in water. When the mass is removed, the cube rises by 2 cm. What is the size of the cube?
Answer» A cube of wood supporting a mass of 200 g just floats in water. When the mass is removed, the cube rises by 2 cm. What is the size of the cube?

Discussion

2.	Two small particles of equal masses start moving in opposite directions from a point A in a horizontal circular orbit. Their tangential velocities are V and 2V respectively, as shown in the figure. Between collisions, the particles move with constant speeds. After making how many elastic collisions, other than that at A, these two particulars will again reach the point A?
Answer» Two small particles of equal masses start moving in opposite directions from a point $A$ in a horizontal circular orbit. Their tangential velocities are $V$ and $2 V$ respectively, as shown in the figure. Between collisions, the particles move with constant speeds. After making how many elastic collisions, other than that at $A$ , these two particulars will again reach the point $A$ ?

Discussion

3.	A stone weighing 3 kg falls from the top of a tower 100 m high and buries itself 2 m deep in sand. Find the time (in seconds) of penetration (g=10 m/s2)
Answer» A stone weighing $3 k g$ falls from the top of a tower $100 m$ high and buries itself $2 m$ deep in sand. Find the time (in seconds) of penetration $(g = 10 m / s^{2})$

Discussion

4.	A man moving with velocity 5 m/s along a straight line observes rain falling vertically at the rate of 10 m/s. Find the speed of rain with respect to ground, and angle(θ) made from vertical by the rain as seen from ground.
Answer» A man moving with velocity $5 m/s$ along a straight line observes rain falling vertically at the rate of $10 m/s$ . Find the speed of rain with respect to ground, and angle $(θ)$ made from vertical by the rain as seen from ground.

Discussion

5.	An arrow is thrown in the air it's time of flight is 5 second and the range is 200 m. Determine( a )the vertical component of the velocity of projection (b)the horizontal component (c) maximum height (d) the angle made with the horizontal.(g= 9.8m/s2)
Answer» An arrow is thrown in the air it's time of flight is 5 second and the range is 200 m. Determine( a )the vertical component of the velocity of projection (b)the horizontal component (c) maximum height (d) the angle made with the horizontal.(g= 9.8m/s^2₎

Discussion

6.	A long wire carrying a steady current is bent into a circular loop of one turn. The magnetic field at the centre of the loop is B. It is then bent into a circular coil of n turns, find the magnetic field at the centre of this coil.
Answer» A long wire carrying a steady current is bent into a circular loop of one turn. The magnetic field at the centre of the loop is B. It is then bent into a circular coil of n turns, find the magnetic field at the centre of this coil.

Discussion

7.	sir, If a question is given like this A stone is dropped from a height of 49m .what will be its velocity when it has drokpped half the height ? Ans:- u=0 h=49 a=9.8m/s Sqr vSqr=uSqr+2gh = 0+29.849 in this step we should do 49/2 or not?
Answer» sir, If a question is given like this A stone is dropped from a height of 49m .what will be its velocity when it has drokpped half the height ? Ans:- u=0 h=49 a=9.8m/s Sqr vSqr=uSqr+2gh = 0+29.849 in this step we should do 49/2 or not?

Discussion

8.	200 mL of a strong acid solution of pH = 2.0 is mixed with 800 mL of another acid solution of pH = 3.0. The pH of resultant solution is
Answer» 200 mL of a strong acid solution of pH = 2.0 is mixed with 800 mL of another acid solution of pH = 3.0. The pH of resultant solution is

Discussion

9.	Can the mass of a body change when it travels at a speed of light ?
Answer» Can the mass of a body change when it travels at a speed of light ?

Discussion

10.	If ω=1, the value of impedance of the given circuit is
Answer» If $ω = 1,$ the value of impedance of the given circuit is

Discussion

11.	A square metal wire loop of side 10 cm and resistance 1 Ω is moved with a constant velocity v in a uniform magnetic field B = 2 T, as shown in Fig. 25.4. The loop is connected to 4 Ω resistor. What should be the speed v of the loop as to have a steady current of 1 mA in the loop ?
Answer» A square metal wire loop of side 10 cm and resistance 1 $Ω$ is moved with a constant velocity v in a uniform magnetic field B = 2 T, as shown in Fig. 25.4. The loop is connected to 4 $Ω$ resistor. What should be the speed v of the loop as to have a steady current of 1 mA in the loop ?

Discussion

12.	In the absence of an external torque on a system, which of the following will not change?
Answer» In the absence of an external torque on a system, which of the following will not change?

Discussion

13.	A block of weight 5 N is pushed against a vertical wall by a force 12 N. The coefficient of friction between the wall and block is 0.6. The magnitude of the force exerted by the wall on the block is
Answer» A block of weight $5 N$ is pushed against a vertical wall by a force $12 N$ . The coefficient of friction between the wall and block is 0.6. The magnitude of the force exerted by the wall on the block is

Discussion

14.	If the potential difference between the plates of a capacitor is increased by 20%, the energy stored in the capacitor increases by exactly
Answer» If the potential difference between the plates of a capacitor is increased by 20%, the energy stored in the capacitor increases by exactly

Discussion

15.	A parallel plate condenser has a capacitance 50μF in air and 110μF when immersed in an oil. The dielectric constant of the oil is?
Answer» A parallel plate condenser has a capacitance 50μF in air and 110μF when immersed in an oil. The dielectric constant of the oil is?

Discussion

16.	In the given system, a capacitor of plate area A is charged upto charge q the mass of each plate is m2, the lower plate is rigidly fixed. Find the value of m1 so that the system is in equilibrium.
Answer» In the given system, a capacitor of plate area $A$ is charged upto charge $q$ the mass of each plate is $m_{2}$ , the lower plate is rigidly fixed. Find the value of $m_{1}$ so that the system is in equilibrium.

Discussion

17.	Displacement does not have direction as it is the shortest distance between initial and starting point; then why is displacement a vector quantity and distance a scalar quantity?
Answer» Displacement does not have direction as it is the shortest distance between initial and starting point; then why is displacement a vector quantity and distance a scalar quantity?

Discussion

18.	Find the maximum force F to be applied for the system shown, so that the two blocks move together. Take g=10 m/s2.
Answer» Find the maximum force $F$ to be applied for the system shown, so that the two blocks move together. Take $g = 10 {m/s}^{2}$ .

Discussion

19.	A door 1.6 m wide requires a minimum force of 1 N to be applied at the free end to open or close it. The minimum force that is required at a point 0.4 m away from the hinges for opening or closing the door is
Answer» A door $1.6 m$ wide requires a minimum force of $1 N$ to be applied at the free end to open or close it. The minimum force that is required at a point $0.4 m$ away from the hinges for opening or closing the door is

Discussion

20.	A block begins to slide down a rough inclined plane of angle 45∘ and moves 1 m in 4√2 s. What is the coefficient of friction μ, between the plane and the block? (Take g=10 m/s2)
Answer» A block begins to slide down a rough inclined plane of angle $45^{\circ}$ and moves $1 m$ in $\sqrt[4]{2} s$ . What is the coefficient of friction $μ$ , between the plane and the block? (Take $g = 10 m / s^{2})$

Discussion

21.	A transverse sinusoidal wave moves along a string in the positive x−direction at a speed of 10 cm/s. The wavelength of the wave is 0.5 m and its amplitude is 10 cm. At a particular time t, the snapshot of the wave is shown in the figure. The velocity of a particle at P when its displacement is 5 cm along y−axis is
Answer» A transverse sinusoidal wave moves along a string in the positive $x -$ direction at a speed of $10 cm/s$ . The wavelength of the wave is $0.5 m$ and its amplitude is $10 cm$ . At a particular time $t$ , the snapshot of the wave is shown in the figure. The velocity of a particle at $P$ when its displacement is $5 cm$ along $y -$ axis is

Discussion

22.	Consider the cyclic process ABCA as shown in the figure, performed on a sample of 2.0 mole of an ideal gas. A total of 1200 J of heat is withdrawn from the sample in the process. Find the magnitude of the work done (in joules) by the gas during the part BC. (R=8.3 JK−1mol−1)
Answer» Consider the cyclic process $A B C A$ as shown in the figure, performed on a sample of $2.0$ mole of an ideal gas. A total of $1200 J$ of heat is withdrawn from the sample in the process. Find the magnitude of the work done (in joules) by the gas during the part $B C$ . $(R = 8.3 {JK}^{- 1} {mol}^{- 1})$

Discussion

23.	Explain the mechanism of the magnetism in the current flow
Answer» Explain the mechanism of the magnetism in the current flow

Discussion

24.	Why is semiconductor damaged by strong current?
Answer» Why is semiconductor damaged by strong current?

Discussion

25.	A tank is filled with water upto a height H. Water is allowed to come out of a hole P in one of the walls at a depth h below the surface of water as shown in figure. Express the horizontal distance X in terms of H and h
Answer» A tank is filled with water upto a height H. Water is allowed to come out of a hole P in one of the walls at a depth h below the surface of water as shown in figure. Express the horizontal distance X in terms of H and h

Discussion

26.	What is shear stress?
Answer» What is shear stress?

Discussion

27.	3 moles of an ideal gas are contained within a cylinder with a frictionless piston and are initially at temperature T. The pressure of the gas remains constant, while its volume gets doubled. If R is the molar gas constant, the work done by the gas in this process is
Answer» $3$ moles of an ideal gas are contained within a cylinder with a frictionless piston and are initially at temperature $T$ . The pressure of the gas remains constant, while its volume gets doubled. If $R$ is the molar gas constant, the work done by the gas in this process is

Discussion

28.	Figure shows a container filled with a liquid of density ρ. Four points A,B,C and D lie on the diametrically opposite points of a circle as shown. Points A and C lie on a vertical line and points B and D lie on a horizontal line. PA,PB,PC,PD are the absolute pressures at the respective points. Then, the correct statement(s) is/are :
Answer» Figure shows a container filled with a liquid of density $ρ$ . Four points $A, B, C and D$ lie on the diametrically opposite points of a circle as shown. Points $A$ and $C$ lie on a vertical line and points $B$ and $D$ lie on a horizontal line. $P_{A}, P_{B}, P_{C}, P_{D}$ are the absolute pressures at the respective points. Then, the correct statement(s) is/are :

Discussion

29.	Is it necessary for every magnetic field configuration to have a north and south pole? Justify
Answer» Is it necessary for every magnetic field configuration to have a north and south pole? Justify

Discussion

30.	Two refrigerators A and B work between - 20. C and 25 .C and between - 10 C and 25 C respectively. Which one is the better refrigerator?
Answer» Two refrigerators A and B work between - 20^.C and 25 ^.C and between - 10 C and 25 C respectively. Which one is the better refrigerator?

Discussion

31.	A horizontal force F pulls a 10kg carton across the floor at a constant speed. If the coefficient of sliding friction between carton and floor is 0.50, the work done by F in moving the carton through 5m is
Answer» A horizontal force F pulls a 10kg carton across the floor at a constant speed. If the coefficient of sliding friction between carton and floor is 0.50, the work done by F in moving the carton through 5m is

Discussion

32.	How do polarised glasses work?
Answer» How do polarised glasses work?

Discussion

33.	Let →u and →v be unit vectors. If →w is a vector such that →w+(→w×→u)=→v, then maximum value of 2\|(→u×→v).→w\| is
Answer» Let $\to u$ and $\to v$ be unit vectors. If $\to w$ is a vector such that $\to w + (\to w \times \to u) = \to v$ , then maximum value of $2 \| (\to u \times \to v) . \to w \|$ is

Discussion

34.	On a smooth horizontal table, 2 blocks of mass 20 kg and 10 kg are placed in contact. A horizontal force of 5 N is applied to the 20 kg block. With what force will this block press the 10 kg block?
Answer» On a smooth horizontal table, 2 blocks of mass 20 kg and 10 kg are placed in contact. A horizontal force of 5 N is applied to the 20 kg block. With what force will this block press the 10 kg block?

Discussion

35.	The equation of a wave is y=sin π(0.5x−200t) , where x and y are expressed in cm and t in sec. The wave velocity is [MP PMT 1986]
Answer» The equation of a wave is $y = s i n π (0.5 x - 200 t)$ , where x and y are expressed in cm and t in sec. The wave velocity is [MP PMT 1986]

35.

The equation of a wave is y=sin π(0.5x−200t) , where x and y are expressed in cm and t in sec. The wave velocity is [MP PMT 1986]

Answer»

The equation of a wave is $y = s i n π (0.5 x - 200 t)$ , where x and y are expressed in cm and t in sec. The wave velocity is

[MP PMT 1986]

Discussion

36.	Difference in height of the liquid columns in the limbs of a rotating U− tube as shown in the figure is: (Neglect the width of each limb and take g=10 m/s2)
Answer» Difference in height of the liquid columns in the limbs of a rotating $U -$ tube as shown in the figure is: (Neglect the width of each limb and take $g = 10 {m/s}^{2}$ )

Discussion

37.	A wagon weighing 1000 kg is moving with a velocity 50km/h on smooth horizontal rails. A mass of 250 kg is dropped into it. The velocity with which it moves now is
Answer» A wagon weighing 1000 kg is moving with a velocity 50km/h on smooth horizontal rails. A mass of 250 kg is dropped into it. The velocity with which it moves now is

Discussion

38.	Figure below shows a circuit which may be used to compare the resistance R of an unknown resistor with a 100 Ω standard. The distances l from one end of the potentiometer slider wire to the balance point are 400 mm and 588 mm when X is connected to Y and Z respectively. The length of the slide is 1.00 m. What is the value of resistance R?
Answer» Figure below shows a circuit which may be used to compare the resistance $R$ of an unknown resistor with a $100 Ω$ standard. The distances $l$ from one end of the potentiometer slider wire to the balance point are 400 mm and 588 mm when X is connected to Y and Z respectively. The length of the slide is 1.00 m. What is the value of resistance R?

Discussion

39.	The magnitude of components of a vector →a along x and y axis respectively are
Answer» The magnitude of components of a vector $\to a$ along x and y axis respectively are

Discussion

40.	Define mutual inductance between a pair of coils. Derive an expression for the mutual inductance of two long coaxial solenoids of same length wound one over the other.
Answer» Define mutual inductance between a pair of coils. Derive an expression for the mutual inductance of two long coaxial solenoids of same length wound one over the other.

Discussion

41.	A potential difference of 6V is applied to a coil inductance 0.5H and a resistance of 4 ohm connected in series. The time taken for the current to reach half the maximum value is (in seconds)
Answer» A potential difference of 6V is applied to a coil inductance 0.5H and a resistance of 4 ohm connected in series. The time taken for the current to reach half the maximum value is (in seconds)

Discussion

42.	A rod of mass m and length L, lying horizontally, is free to rotate about a vertical axis through its centre. A horizontal force of constant magnitude F acts on the rod at a distance of L4 from the centre. The force is always perpendicular to the rod. Find the angle rotated by the rod during the time l after the motion starts.
Answer» A rod of mass m and length L, lying horizontally, is free to rotate about a vertical axis through its centre. A horizontal force of constant magnitude F acts on the rod at a distance of $\frac{L}{4}$ from the centre. The force is always perpendicular to the rod. Find the angle rotated by the rod during the time l after the motion starts.

Discussion

43.	The fundamental frequency of a closed pipe is 293 Hz when the air in it is at a temperature of 20∘C. What will be its fundamental frequency when the temperature changes to 22∘C ?
Answer» The fundamental frequency of a closed pipe is 293 Hz when the air in it is at a temperature of $20^{\circ} C$ . What will be its fundamental frequency when the temperature changes to $22^{\circ} C$ ?

Discussion

44.	A charge of 1.0 C is oplaced at the top of your college building and another equal charge at the top of your house. Take the separation between the two charges to be 2.0 km. Find the force exerted by the charges on each other. How many teimes of your weight is this force?
Answer» A charge of 1.0 C is oplaced at the top of your college building and another equal charge at the top of your house. Take the separation between the two charges to be 2.0 km. Find the force exerted by the charges on each other. How many teimes of your weight is this force?

Discussion

45.	A force F=(6i cap - 8j cap + 10 k cap)N produces an acceleration of 1 m/ second square in a body. The mass of the body would be: (A) 200 kg (B) 20 kg. (C) 10√2 kg. (D) 6√2 kg
Answer» A force F=(6i cap - 8j cap + 10 k cap)N produces an acceleration of 1 m/ second square in a body. The mass of the body would be: (A) 200 kg (B) 20 kg. (C) 10√2 kg. (D) 6√2 kg

Discussion

46.	In a horizontal spring mass system, mass m is released after being displaced towards right by some distance at t=0 on a frictionless surface. The phase angle of the motion in radian when it passes through the equilibrium position for the first time is
Answer» In a horizontal spring mass system, mass $m$ is released after being displaced towards right by some distance at $t = 0$ on a frictionless surface. The phase angle of the motion in radian when it passes through the equilibrium position for the first time is

Discussion

47.	Which of the following equations represents a transverse wave travelling along Y-axis?
Answer» Which of the following equations represents a transverse wave travelling along Y-axis?

Discussion

48.	A body, moving in a straight line with an initial velocity of 5 ms−1 and a constant acceleration, covers a distance of 30 m in the 3rd second. How much distance will it cover in the next 2 seconds?
Answer» A body, moving in a straight line with an initial velocity of $5 {ms}^{- 1}$ and a constant acceleration, covers a distance of $30 m$ in the $3^{r d}$ second. How much distance will it cover in the next $2$ seconds?

Discussion

49.	Let PM be the perpendicular from the point P(1, 2, 3) to xy plane. If OP makes an angle θ with the +ve direction of the z-axis and OM makes an angle ϕ with the positive direction of x-axis, where O is the origin then (θ and ϕ are acute angles)
Answer» Let PM be the perpendicular from the point P(1, 2, 3) to $x y$ plane. If OP makes an angle $θ$ with the +ve direction of the z-axis and OM makes an angle $ϕ$ with the positive direction of x-axis, where O is the origin then ( $θ$ and $ϕ$ are acute angles)

Discussion

50.	A tank cart is filled with water as shown in the figure. The initial mass of the cart with water is m0=100 kg. At time t=0, a hole is made in the left wall of the cart and water starts spilling out from the cart, with a constant velocity of vr=10 m/s with respect to the cart. The rate of ejection of water is r=2 kg/s. Find the acceleration of the cart after time t=5 s.
Answer» A tank cart is filled with water as shown in the figure. The initial mass of the cart with water is $m_{0} = 100 kg$ . At time $t = 0$ , a hole is made in the left wall of the cart and water starts spilling out from the cart, with a constant velocity of $v_{r} = 10 m/s$ with respect to the cart. The rate of ejection of water is $r = 2 kg/s$ . Find the acceleration of the cart after time $t = 5 s$ .

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A cube of wood supporting a mass of 200 g just floats in water. When the mass is removed, the cube rises by 2 cm. What is the size of the cube?

A stone weighing 3 kg falls from the top of a tower 100 m high and buries itself 2 m deep in sand. Find the time (in seconds) of penetration (g=10 m/s2)

A man moving with velocity 5 m/s along a straight line observes rain falling vertically at the rate of 10 m/s. Find the speed of rain with respect to ground, and angle(θ) made from vertical by the rain as seen from ground.

An arrow is thrown in the air it's time of flight is 5 second and the range is 200 m. Determine( a )the vertical component of the velocity of projection (b)the horizontal component (c) maximum height (d) the angle made with the horizontal.(g= 9.8m/s2)

A long wire carrying a steady current is bent into a circular loop of one turn. The magnetic field at the centre of the loop is B. It is then bent into a circular coil of n turns, find the magnetic field at the centre of this coil.

sir, If a question is given like this A stone is dropped from a height of 49m .what will be its velocity when it has drokpped half the height ? Ans:- u=0 h=49 a=9.8m/s Sqr vSqr=uSqr+2gh = 0+2*9.8*49 in this step we should do 49/2 or not?

200 mL of a strong acid solution of pH = 2.0 is mixed with 800 mL of another acid solution of pH = 3.0. The pH of resultant solution is

Can the mass of a body change when it travels at a speed of light ?

If ω=1, the value of impedance of the given circuit is

A square metal wire loop of side 10 cm and resistance 1 Ω is moved with a constant velocity v in a uniform magnetic field B = 2 T, as shown in Fig. 25.4. The loop is connected to 4 Ω resistor. What should be the speed v of the loop as to have a steady current of 1 mA in the loop ?

In the absence of an external torque on a system, which of the following will not change?

A block of weight 5 N is pushed against a vertical wall by a force 12 N. The coefficient of friction between the wall and block is 0.6. The magnitude of the force exerted by the wall on the block is

If the potential difference between the plates of a capacitor is increased by 20%, the energy stored in the capacitor increases by exactly

A parallel plate condenser has a capacitance 50μF in air and 110μF when immersed in an oil. The dielectric constant of the oil is?

In the given system, a capacitor of plate area A is charged upto charge q the mass of each plate is m2, the lower plate is rigidly fixed. Find the value of m1 so that the system is in equilibrium.

Displacement does not have direction as it is the shortest distance between initial and starting point; then why is displacement a vector quantity and distance a scalar quantity?

Find the maximum force F to be applied for the system shown, so that the two blocks move together. Take g=10 m/s2.

A door 1.6 m wide requires a minimum force of 1 N to be applied at the free end to open or close it. The minimum force that is required at a point 0.4 m away from the hinges for opening or closing the door is

A block begins to slide down a rough inclined plane of angle 45∘ and moves 1 m in 4√2 s. What is the coefficient of friction μ, between the plane and the block? (Take g=10 m/s2)

Consider the cyclic process ABCA as shown in the figure, performed on a sample of 2.0 mole of an ideal gas. A total of 1200 J of heat is withdrawn from the sample in the process. Find the magnitude of the work done (in joules) by the gas during the part BC. (R=8.3 JK−1mol−1)

Explain the mechanism of the magnetism in the current flow

Why is semiconductor damaged by strong current?

A tank is filled with water upto a height H. Water is allowed to come out of a hole P in one of the walls at a depth h below the surface of water as shown in figure. Express the horizontal distance X in terms of H and h

What is shear stress?

3 moles of an ideal gas are contained within a cylinder with a frictionless piston and are initially at temperature T. The pressure of the gas remains constant, while its volume gets doubled. If R is the molar gas constant, the work done by the gas in this process is

Is it necessary for every magnetic field configuration to have a north and south pole? Justify

Two refrigerators A and B work between - 20​​​​​​. C and 25 ​​​​​​.C and between - 10 C and 25 C respectively. Which one is the better refrigerator?

A horizontal force F pulls a 10kg carton across the floor at a constant speed. If the coefficient of sliding friction between carton and floor is 0.50, the work done by F in moving the carton through 5m is

How do polarised glasses work?

Let →u and →v be unit vectors. If →w is a vector such that →w+(→w×→u)=→v, then maximum value of 2|(→u×→v).→w| is

On a smooth horizontal table, 2 blocks of mass 20 kg and 10 kg are placed in contact. A horizontal force of 5 N is applied to the 20 kg block. With what force will this block press the 10 kg block?

The equation of a wave is y=sin π(0.5x−200t) , where x and y are expressed in cm and t in sec. The wave velocity is [MP PMT 1986]

Difference in height of the liquid columns in the limbs of a rotating U− tube as shown in the figure is: (Neglect the width of each limb and take g=10 m/s2)

A wagon weighing 1000 kg is moving with a velocity 50km/h on smooth horizontal rails. A mass of 250 kg is dropped into it. The velocity with which it moves now is

The magnitude of components of a vector →a along x and y axis respectively are

Define mutual inductance between a pair of coils. Derive an expression for the mutual inductance of two long coaxial solenoids of same length wound one over the other.

A potential difference of 6V is applied to a coil inductance 0.5H and a resistance of 4 ohm connected in series. The time taken for the current to reach half the maximum value is (in seconds)

The fundamental frequency of a closed pipe is 293 Hz when the air in it is at a temperature of 20∘C. What will be its fundamental frequency when the temperature changes to 22∘C ?

A charge of 1.0 C is oplaced at the top of your college building and another equal charge at the top of your house. Take the separation between the two charges to be 2.0 km. Find the force exerted by the charges on each other. How many teimes of your weight is this force?

A force F=(6i cap - 8j cap + 10 k cap)N produces an acceleration of 1 m/ second square in a body. The mass of the body would be: (A) 200 kg (B) 20 kg. (C) 10√2 kg. (D) 6√2 kg

In a horizontal spring mass system, mass m is released after being displaced towards right by some distance at t=0 on a frictionless surface. The phase angle of the motion in radian when it passes through the equilibrium position for the first time is

Which of the following equations represents a transverse wave travelling along Y-axis?

A body, moving in a straight line with an initial velocity of 5 ms−1 and a constant acceleration, covers a distance of 30 m in the 3rd second. How much distance will it cover in the next 2 seconds?

Let PM be the perpendicular from the point P(1, 2, 3) to xy plane. If OP makes an angle θ with the +ve direction of the z-axis and OM makes an angle ϕ with the positive direction of x-axis, where O is the origin then (θ and ϕ are acute angles)

sir, If a question is given like this A stone is dropped from a height of 49m .what will be its velocity when it has drokpped half the height ? Ans:- u=0 h=49 a=9.8m/s Sqr vSqr=uSqr+2gh = 0+29.849 in this step we should do 49/2 or not?

Two refrigerators A and B work between - 20. C and 25 .C and between - 10 C and 25 C respectively. Which one is the better refrigerator?