125876 + Interview Questions in General QA

1.	What are the precautions to be followed while riding a bicycle?
Answer» Safe Cycling: 1. Ride close to the road in single file. If there is a cycle track, use it. 2. A cyclist should ride close the the kerb on the left and be careful about drainage pits that may in some case be without a cover. 3. Try to avoid s road with heavy traffic. 4. Always keep safe lateral distance from heavy vehicles as the wind turbulence created by them may throw a cyclist out of balance. 5. Do not fide at high speed especially on wet roads. 6. Before you start, stop or trun, use hand signals to indicate your intentions. And only if safe, move on. 7. Follow traffic signals at all junctions. Don’t cross when the signal is red, slow down at intersections. 8. Look out for vehicles at intersections. Look behind and cross only when there is enough gap. 9. Have a reflector or light while riding at night. 10. Most importantly, learn perfectly all signs and signals and obey them faithfully when you use your cycle.

1.

What are the precautions to be followed while riding a bicycle?

Answer»

Safe Cycling:

1. Ride close to the road in single file. If there is a cycle track, use it.

2. A cyclist should ride close the the kerb on the left and be careful about drainage pits that may in some case be without a cover.

3. Try to avoid s road with heavy traffic.

4. Always keep safe lateral distance from heavy vehicles as the wind turbulence created by them may throw a cyclist out of balance.

5. Do not fide at high speed especially on wet roads.

6. Before you start, stop or trun, use hand signals to indicate your intentions. And only if safe, move on.

7. Follow traffic signals at all junctions. Don’t cross when the signal is red, slow down at intersections.

8. Look out for vehicles at intersections. Look behind and cross only when there is enough gap.

9. Have a reflector or light while riding at night.

10. Most importantly, learn perfectly all signs and signals and obey them faithfully when you use your cycle.

Discussion

2.	What are the rules followed by motor cyclists?
Answer» 1. Must hold a valid driving license and required documents. 2. Wearing a helmet is compulsory both for the rider and the pillion rider. 3. Pillion rider should not disturb the rider.

2.

What are the rules followed by motor cyclists?

Answer»

1. Must hold a valid driving license and required documents.

2. Wearing a helmet is compulsory both for the rider and the pillion rider.

3. Pillion rider should not disturb the rider.

Discussion

3.	As per Section 37 of the Indian Partnership Act, 1932, the executors would be entitled at their choice to the interest calculated from the date of death till the date of payment of the final amount due to the decreased partner atA. 6% p.aB. 7% p.aC. 8% p.aD. 10% p.a
Answer» Correct Answer - A

Discussion

4.	Define calorific value
Answer» The amount of heat given out by a unit mass of a fuel on complete combustion is called calorific value.

Discussion

5.	How is coal formed?
Answer» Coal is formed by the slow decomposition of forest woods that got buried under the earth’s crust due to natural calamities. Heat and pressure over millions of years changed these plants to coal.

Discussion

6.	What is blind spot?
Answer» The point where the optic nerve enters the eye has which no nerve endings. It is insensitive to light and is called blind spot.

Discussion

7.	When an object is placed within the focal length of the convex lens, where does its ‘image will form?
Answer» When an object is placed within the focal length of a convex lens a virtual, erect and magnified image is formed.

Discussion

8.	Why are stars twinkling in night?
Answer» The layers of atmosphere have different densities so have different coefficients of refraction. The light coming from stars deviates continuously after passing through these different atmospheric layers. That is why the stars seem twinkling in night.

Discussion

9.	Define the principal focus of a concave lens
Answer» The principal focus of a concave lens is a point on its principal axis from which light rays, originally parallel to the axis, appear to diverge after passing through the lens.

Discussion

10.	Define principal axis, principal focus and focal length of a convex lens.
Answer» Principle axis: The principal axis of a lens is a line passing throught the optical centre of the lens and perpendicular to both the faces of the lens. Principle focus: The principal focus of a convex lens is a point on its principal axis to which light rays parallel to the principal axis converge after passing through the lens. Focal length: The distance of the principle focus from the optical center of a lens is called its focal length.

Discussion

11.	A cube of aluminium of each side 0.1 m is subjected to a shearing force of 100 N. The top face of the cube is displaced through 0.02 cm with respect to the bottom face. The shearing strain would be(A) 0.02 (B) 0.1 (C) 0.005 (D) 0.002
Answer» Correct option is: (D) 0.002

Discussion

12.	A ray of light incident at an angle θ on a refracting face of a prism emerges from the other face normally. If the angle of the prism is 5° and the prism is made of a material of refractive index 1.5, the angle of incidence is (a) 7.5°. (b) 5°. (c) 15°. (d) 2.5°.
Answer» the angle of incidence is 2.5°.

Discussion

13.	In an ac circuit, the current is given by i = 4 sin (100 πt + 30º) ampere. The current becomes maximum first time (after t = 0) at t equal to :
Answer» when i = 4 sin(2π + 30) then again current will be maximum and it will be when 2π = 100πt means t = 1/50

13.

In an ac circuit, the current is given by i = 4 sin (100 πt + 30º) ampere. The current becomes maximum first time (after t = 0) at t equal to :

Answer»

when i = 4 sin(2π + 30)

then again current will be maximum and it will be

when 2π = 100πt

means t = 1/50

Discussion

14.	A parallel plate capacitor is made of two dielectric blocks in series. One of the blocks has thickness d1 and dielectric constant k1 and the other has thickness d2 and dielectric constant k2 as shown in Fig. 2.3. This arrangement can be thought as a dielectric slab of thickness d (= d1+d2) and effective dielectric constant k. The k is
Answer» (c) k₁k₂(d₁+d₂) / (k₁d₁+k₂d₂)

Discussion

15.	On the valid performance of the contractual obligations by the parties, the contract ………(a) Is discharged (b) Become enforceable (c) Becomes void (d) Becomes legal
Answer» (a) Is discharged

Discussion

16.	A, B, C jointly promised to pay Rs.50,000 to D. Before performance of the contract, C dies. Here, the contract ………(a) Becomes void on C’s death(b) Should be performed by A and B along with C’s legal representatives. (c) Should be performed by A and B alone. (d) Should be renewed between A, B and D.
Answer» (b) Should be performed by A and B along with C’s legal representatives.

Discussion

17.	Which of the following persons can perform the contract?(a) Promisor alone (b) Legal representatives of promisor (c) Agent of the promisor (d) All the above
Answer» (d) All the above

Discussion

18.	What is a Valid tender?
Answer» A valid tender of performance is considered to be the performance of a promise.

Discussion

19.	Explain rules relating to place of performance of promise.
Answer» Time and place of Performance of Promise: It is only the promisee for whom the contract is performed. Only the promisee can demand the performance of the promise under a contract. For Example: X promises Y to pay Z Rs 10,000/-. X does not pay the sum to Z. Here Z cannot bind X for the payment. It is only promisee Y who can enforce the promise against the promisor X. Of course, there are certain special cases, where a third party can enforce a promise though he is not a party to the contract For example in respect of trust, marriage settlement etc. In case of death of promisee, the representative appointed by him can ask for the performance of the promise under a contract.

19.

Explain rules relating to place of performance of promise.

Answer»

Time and place of Performance of Promise: It is only the promisee for whom the contract is performed. Only the promisee can demand the performance of the promise under a contract.

For Example: X promises Y to pay Z Rs 10,000/-. X does not pay the sum to Z. Here Z cannot bind X for the payment. It is only promisee Y who can enforce the promise against the promisor X. Of course, there are certain special cases, where a third party can enforce a promise though he is not a party to the contract

For example in respect of trust, marriage settlement etc. In case of death of promisee, the representative appointed by him can ask for the performance of the promise under a contract.

Discussion

20.	Who is a Joint Promisors?
Answer» Joint Promisors: (a) Devolution of Joint Liabilities (Section 42) Section 42 of Indian Contract Act lays down that “When two or more persons have made a joint promise, then unless a contrary intention appears in the contract, all such persons, during their joint lives and after the death of the last survivor, representatives of all, jointly must fulfil the promise” (b) Devolution of Joint Rights (Section 45) “When a person has made a promise to two or more persons jointly, then unless there is a contract to the contrary, the right to claim performance rests as between him and them, with them during their joint lives and after the death of them with representatives of such deceased person jointly with survivors, and after the death of last survivor, with the representatives of all jointly”.

20.

Who is a Joint Promisors?

Answer»

Joint Promisors:

(a) Devolution of Joint Liabilities (Section 42) Section 42 of Indian Contract Act lays down that “When two or more persons have made a joint promise, then unless a contrary intention appears in the contract, all such persons, during their joint lives and after the death of the last survivor, representatives of all, jointly must fulfil the promise”

(b) Devolution of Joint Rights (Section 45) “When a person has made a promise to two or more persons jointly, then unless there is a contract to the contrary, the right to claim performance rests as between him and them, with them during their joint lives and after the death of them with representatives of such deceased person jointly with survivors, and after the death of last survivor, with the representatives of all jointly”.

Discussion

21.	By whom must contracts be performed?
Answer» 1. Promisor himself 2. Agent 3. Representations 4. Third person 5. Joint Promisors

21.

By whom must contracts be performed?

Answer»

1. Promisor himself

2. Agent

3. Representations

4. Third person

5. Joint Promisors

Discussion

22.	Who is a Legal Representative?
Answer» Legal representative can demand Exception performance. Contrary intention appears from the contract. Contract is of a personal nature.

Discussion

23.	If i and r be the angles of incidence and refraction respectively, when the light ray travels from glass to air, then A) i = rB) i >r C) i < r D) none
Answer» Correct option is C) i < r

Discussion

24.	Funds required for purchasing current assets is an example for …………(a) Fixed Capital Requirement (b) Ploughing Back of Profits (c) Working Capital Requirement (d) Lease Financing
Answer» (c) Working Capital Requirement

Discussion

25.	State two advantages of ploughing back profits?
Answer» Retained earnings can be useful in recession, implementation of future plans, purchasing new assets, etc.

Discussion

26.	What is retained profit or ploughing back profits?
Answer» In good times of business a company makes quite good profits. In such times instead of distributing the entire profit as dividend company saves i.e. retains some part of profit for future business needs. This is profit or ploughing back profits.

Discussion

27.	Two capacitor c1 = 2μf and c2 = 4μf are connected in series and a potential difference (p.d) of 1200 v is applied across it the potential difference across 2μf will beA) 400 V B) 600 V C) 800 V D) 900 V
Answer» The correct option is C) 800 V. Total capacitance equivalent = 2 × 4/ (2 + 4) = 8/6 = 4/3 Q = CV Q = 1200 x 4/3 Q = 1600 V = q/V V = 1600/2 V = 800

27.

Two capacitor c1 = 2μf and c2 = 4μf are connected in series and a potential difference (p.d) of 1200 v is applied across it the potential difference across 2μf will beA) 400 V B) 600 V C) 800 V D) 900 V

Answer»

The correct option is C) 800 V.

Total capacitance equivalent = 2 × 4/ (2 + 4) = 8/6 = 4/3

Q = CV

Q = 1200 x 4/3

Q = 1600

V = q/V

V = 1600/2

V = 800

Discussion

28.	64 identical drops each of capacity 5μF combine to form a big drop. Capacity of the big drop will A) 4μF B) 25μF C) 20μF D) 164 μF
Answer» The correct option is C) 20μF. We first find volume of big drop Volume of big drop = 64 x volume of small drop 4/3 π.R³ =64 x 4/3 π.r³ R = 4r Because capacitance of solid spherical body directly proportion to radius Hence big drop capacitance = 4 x capacitance of small Capacitance of big drop=20μF

28.

64 identical drops each of capacity 5μF combine to form a big drop. Capacity of the big drop will A) 4μF B) 25μF C) 20μF D) 164 μF

Answer»

The correct option is C) 20μF.

We first find volume of big drop Volume of big drop = 64 x volume of small drop

4/3 π.R³ =64 x 4/3 π.r³

R = 4r

Because capacitance of solid spherical body directly proportion to radius

Hence big drop capacitance = 4 x capacitance of small

Capacitance of big drop=20μF

Discussion

29.	64 identical drops each of capacity 5μF combine to form a big drop. Capacity of the big drop will beA. 4μF B. 25μF C. 20μF D. 164μF
Answer» The Correct option is C. 20μF

Discussion

30.	Which one is the internal source? (a) Retained earnings (b) Shares (c) Debentures (d) Public deposits
Answer» (a) Retained earnings

Discussion

31.	The average profit earned by the firm is Rs. 80,000 which includes under valuation of stock an average basis the capital invested in the business and normal rate of return is 8%. Calculate the goodwill of the firm on the basis of times the super profit.
Answer» Average profit – Rs. 80,000 (A) Undervalue of stock – Rs. 8,000 Actual Average profit – Rs. 88,000 Normal profit = Capital investment x Normal rate of return = Rs. 88,000 – Rs. 64,000 = Rs. 24,000 Goodwill = Super profit x 7 = Rs. 24,000 x 7 = Rs. 1,68,000

31.

The average profit earned by the firm is Rs. 80,000 which includes under valuation of stock an average basis the capital invested in the business and normal rate of return is 8%. Calculate the goodwill of the firm on the basis of times the super profit.

Answer»

Average profit – Rs. 80,000

(A) Undervalue of stock – Rs. 8,000

Actual Average profit – Rs. 88,000

Normal profit = Capital investment x Normal rate of return

= Rs. 88,000 – Rs. 64,000

= Rs. 24,000

Goodwill = Super profit x 7

= Rs. 24,000 x 7

= Rs. 1,68,000

Discussion

32.	Funds required for purchasing current assets is an example of (a) Fixed capital requirement (b) Ploughing back of profits (c) Working capital requirement (d) Lease financing
Answer» (c) Working capital requirement

Discussion

33.	The capacitance of parallel plate capacitor........by introduction of dielectric between the plates of the capacitor A) Increases B) Decreases C) Remain same D) 0
Answer» The correct option is A) Increases. The electric field between the plates of parallel plate capacitor is directly proportional to capacitance C of the capacitor. If the total charge on the plates is kept constant, then the potential difference is reduced across the capacitor plates. In this way, dielectric increases the capacitance of the capacitor.

33.

The capacitance of parallel plate capacitor........by introduction of dielectric between the plates of the capacitor A) Increases B) Decreases C) Remain same D) 0

Answer»

The correct option is A) Increases.

The electric field between the plates of parallel plate capacitor is directly proportional to capacitance C of the capacitor.

If the total charge on the plates is kept constant, then the potential difference is reduced across the capacitor plates. In this way, dielectric increases the capacitance of the capacitor.

Discussion

34.	The electric potential in equatorial position of an electric dipole is
Answer» The correct option is (D). For an equatorial point, θ = 90° Cos (θ) = 0 Thus, V = 0

34.

The electric potential in equatorial position of an electric dipole is

Answer»

The correct option is (D).

For an equatorial point,

θ = 90°

Cos (θ) = 0

Thus, V = 0

Discussion

35.	At constant Potential difference, the resistance of any electric circuit is halved; the value of heat produced will beA) Half B) Doubled C) Four times D) Same
Answer» The correct option is B) Doubled. So if resistance decreases, heat produced will increase. Now, here you can see Heat is inversely proportional to resistance. So, if resistance of any electric circuit is halved, then the value of heat produced will be doubled.

35.

At constant Potential difference, the resistance of any electric circuit is halved; the value of heat produced will beA) Half B) Doubled C) Four times D) Same

Answer»

The correct option is B) Doubled.

So if resistance decreases, heat produced will increase.

Now, here you can see Heat is inversely proportional to resistance. So, if resistance of any electric circuit is halved, then the value of heat produced will be doubled.

Discussion

36.	If L be the inductance, R resistance and C be the capacitance of a capacitor, then dimensional formulae of L/R and RC are
Answer» The correct option is (A). If L be the inductance, R resistance and C be the capacitance of a capacitor, then dimensional formulae of L/R and RC M⁰LT^-1, ML⁰T^-1.

36.

If L be the inductance, R resistance and C be the capacitance of a capacitor, then dimensional formulae of L/R and RC are

Answer»

The correct option is (A).

If L be the inductance, R resistance and C be the capacitance of a capacitor, then dimensional formulae of L/R and RC M⁰LT^-1, ML⁰T^-1.

Discussion

37.	The term ‘redeemable’ is used for (a) Preference shares (b) Commercial paper (c) Equity shares (d) Public deposits
Answer» (a) Preference shares

Discussion

38.	The term‘redeemable’ is used for (a) Preference shares (b) Commercial paper (c) Equity shares (d) Public deposits
Answer» (b) Commercial paper

Discussion

39.	Redeemable preference shares can be(A) Redeemed before 20 years(B) Redeemed after 20 years(C) Only partly redeemed after 20 years(D) Both (A) and (B)
Answer» Correct option is (B) Redeemed after 20 years

Discussion

40.	List of the basic units in the SI units.
Answer» The seven basic SI units: (i) Metre (m): One metre is defined as the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second(1983). (ii) Kilogram(kg): It is the mass of a platinum-iridium cylinder (90% Pt and 10%Ir) whose height is equal to its diameter (each=3.9 cm) preserved at International Bureau of Weight and Measures at Sevres (1889). (iii) Second (s.): One second is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the the two hyperfine levels of the ground state of the cesium-133 atom (1967). (iv) Ampere (A): One ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 metre apart in vacuum, would produce between these conductors a force equal to 210^-7 newton per metre of length (1948). (v) Kelvin (K):* One Kelvin is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water (1967). (vi) Candela(cd): Candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 54010²² hertz and that has a radiant intensity in that direction of 1/683 watt per steradian (1979). (vii) Mole (mol):* One mole is the amount of substance of a system, which contains as many elementary antities as there are atoms in 0.012 kilogram of carbon-12(1971).

40.

List of the basic units in the SI units.

Answer»

The seven basic SI units:

(i) Metre (m): One metre is defined as the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second(1983).

(ii) Kilogram(kg): It is the mass of a platinum-iridium cylinder (90% Pt and 10%Ir) whose height is equal to its diameter (each=3.9 cm) preserved at International Bureau of Weight and Measures at Sevres (1889).

(iii) Second (s.): One second is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the the two hyperfine levels of the ground state of the cesium-133 atom (1967).

(iv) Ampere (A): One ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 metre apart in vacuum, would produce between these conductors a force equal to 2*10^-7 newton per metre of length (1948).

(v) Kelvin (K): One Kelvin is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water (1967).

(vi) Candela(cd): Candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540*10²² hertz and that has a radiant intensity in that direction of 1/683 watt per steradian (1979).

(vii) Mole (mol): One mole is the amount of substance of a system, which contains as many elementary antities as there are atoms in 0.012 kilogram of carbon-12(1971).

Discussion

41.	Write the number of significant figures in each of the following measurements1. 1.67 × 10-27 kg2. 0.270 cm
Answer» 1. Three significant figures. 2. Three significant figures.

41.

Write the number of significant figures in each of the following measurements1. 1.67 × 10-27 kg2. 0.270 cm

Answer»

1. Three significant figures.

2. Three significant figures.

Discussion

42.	Name the SI unit of weight.
Answer» SI unit of weight is Newton (N).

Discussion

43.	What are the Advantages of SI units?
Answer» It is a metric, rational coherent and internationally acceptable system of units which covers all branches of physics.

Discussion

44.	Write a note on the SI system.
Answer» SI system represents the “International system of units”. It was adopted in 1971 at the general conference on Weights and Measures : S.I. system has seven fundamental units. They are 1. meter for length, 2. kilogram for mass 3. second for time 4. ampere for electric current 5. Kelvin for temperature 6. candela for luminous intensity 7. mole for Amount of substance. There are 2 supplementary units, They are 1. radian for measurement of angle in a plane. 2. steradian for measurement of angle in solid angle.

44.

Write a note on the SI system.

Answer»

SI system represents the “International system of units”. It was adopted in 1971 at the general conference on Weights and Measures :

S.I. system has seven fundamental units. They are

1. meter for length,

2. kilogram for mass

3. second for time

4. ampere for electric current

5. Kelvin for temperature

6. candela for luminous intensity

7. mole for Amount of substance.

There are 2 supplementary units, They are

1. radian for measurement of angle in a plane.

2. steradian for measurement of angle in solid angle.

Discussion

45.	Show that 1 Joule = 107erg by the method of dimension.
Answer» Let MKS unit of work = n × CGS unit of work. n = MKS unit of work/CGS unit of work = kg m²s^-2/gm cm²s^-2 = kgm²s^-2/10³ kg 10^-4 m²s^-2 = 1/10^-7 ∴ MKS unit of work = 10⁷ CGS unit of work. i.e 1 J = 10⁷ erg.

45.

Show that 1 Joule = 107erg by the method of dimension.

Answer»

Let MKS unit of work

= n × CGS unit of work.

n = MKS unit of work/CGS unit of work

= kg m²s^-2/gm cm²s^-2

= kgm²s^-2/10³ kg 10^-4 m²s^-2 = 1/10^-7

∴ MKS unit of work = 10⁷ CGS unit of work.

i.e 1 J = 10⁷ erg.

Discussion

46.	Why is the speed of whirl wind in a tornado so high?
Answer» In a whirl wind, the air from nearby region gets concentrated in a small space thereby decreasing the value of moment of inertia considerably. Since, I ω= constant, due to decrease in moment of inertia, the angular speed becomes quite high.

Discussion

47.	A dimensionally correct equation need not actually be a correct equation but dimensionally incorrect equation is necessarily wrong. Justify.
Answer» (i) To justify a dimensionally correct equation need not be actually a correct equation, consider equation, v² = 2as Dimensions of L.H.S. = [v²] = [L²M⁰T²] Dimensions of R.H.S. = [as]= [L²M⁰T²] ⇒ [L.H.S.] = [R.H.S.] This implies equation v² = 2as is dimensionally correct. But actual equation is, v²= u² + 2as This confirms a dimensionally correct equation need not be actually a correct equation. (ii) To justify dimensionally incorrect equation is necessarily wrong, consider the formula, \(\frac{1}{2}\) mv = mgh Dimensions of L.H.S. = [mv] = [L¹M¹T^-1] Dimensions of R.H.S. = [mgh] = [L²M¹T^-2] Since the dimensions of R.H.S. and L.H.S. are not equal, the formula given by equation must be incorrect. This confirms dimensionally incorrect equation is necessarily wrong.

47.

A dimensionally correct equation need not actually be a correct equation but dimensionally incorrect equation is necessarily wrong. Justify.

Answer»

(i) To justify a dimensionally correct equation need not be actually a correct equation,

consider equation, v² = 2as

Dimensions of L.H.S. = [v²] = [L²M⁰T²]

Dimensions of R.H.S. = [as]= [L²M⁰T²]

⇒ [L.H.S.] = [R.H.S.]

This implies equation v² = 2as is dimensionally correct.

But actual equation is, v²= u² + 2as

This confirms a dimensionally correct equation need not be actually a correct equation.

(ii) To justify dimensionally incorrect equation is necessarily wrong, consider the formula, \(\frac{1}{2}\) mv = mgh

Dimensions of L.H.S. = [mv] = [L¹M¹T^-1]

Dimensions of R.H.S. = [mgh] = [L²M¹T^-2]

Since the dimensions of R.H.S. and L.H.S. are not equal, the formula given by equation must be incorrect.

This confirms dimensionally incorrect equation is necessarily wrong.

Discussion

48.	Why the speed of whirl wind in a Tornado is alarmingly high?
Answer» In whirl wind, air from regions get concentrated in a small space, so I is considerable less. Since Iω = constant so ω is so high.

Discussion

49.	What is drop is potential energy if M1 goes down by d1∆θ and M2 goes up by d2∆θ in case of two bodies of masses M1 and M2 sitting on a seesaw and balancing each other initially?
Answer» If M₁ goes down by d₁∆θ and M₂ goes up by d₂∆θ then the drop in potential energy is, ∆U = M₂gd₂∆θ - M₁gd₁∆θ ∆U = (F₂d₂ - F₁d₁)∆θ ∵ Mg₂ = F₂ and M₁g = F₁

49.

What is drop is potential energy if M1 goes down by d1∆θ and M2 goes up by d2∆θ in case of two bodies of masses M1 and M2 sitting on a seesaw and balancing each other initially?

Answer»

If M₁ goes down by d₁∆θ and M₂ goes up by d₂∆θ then the drop in potential energy is,

∆U = M₂gd₂∆θ - M₁gd₁∆θ

∆U = (F₂d₂ - F₁d₁)∆θ

∵ Mg₂ = F₂ and M₁g = F₁

Discussion

50.	Check whether the given equation \(F.s=\frac{1}{2}mv^2-\frac{1}{2}mu^2\) is dimensionally correct, or not where, m is mass of the body, v is its final velocity, u is its initial velocity, F is applied force and s is distance covered.
Answer» The dimension of L.H.S. F.s = [MLT^-2 ].[L] =[ML²T^-2] The dimensions of R.H.S. \(\frac{1}{2}mv^2 or \frac{1}{2}mu^2\) = [M][LT^-1]² = [ML²T^-2] So, dimensions of L.H.S.= R.H.S. So, given equation is dimensionally correct.

50.

Check whether the given equation \(F.s=\frac{1}{2}mv^2-\frac{1}{2}mu^2\) is dimensionally correct, or not where, m is mass of the body, v is its final velocity, u is its initial velocity, F is applied force and s is distance covered.

Answer»

The dimension of L.H.S.

F.s = [MLT^-2 ].[L]

=[ML²T^-2]

The dimensions of R.H.S.

\(\frac{1}{2}mv^2 or \frac{1}{2}mu^2\) = [M][LT^-1]²

= [ML²T^-2]

So, dimensions of L.H.S.= R.H.S.

So, given equation is dimensionally correct.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

What are the precautions to be followed while riding a bicycle?

What are the rules followed by motor cyclists?

As per Section 37 of the Indian Partnership Act, 1932, the executors would be entitled at their choice to the interest calculated from the date of death till the date of payment of the final amount due to the decreased partner atA. 6% p.aB. 7% p.aC. 8% p.aD. 10% p.a

Define calorific value

How is coal formed?

What is blind spot?

When an object is placed within the focal length of the convex lens, where does its ‘image will form?

Why are stars twinkling in night?

Define the principal focus of a concave lens

Define principal axis, principal focus and focal length of a convex lens.

A cube of aluminium of each side 0.1 m is subjected to a shearing force of 100 N. The top face of the cube is displaced through 0.02 cm with respect to the bottom face. The shearing strain would be(A) 0.02 (B) 0.1 (C) 0.005 (D) 0.002

A ray of light incident at an angle θ on a refracting face of a prism emerges from the other face normally. If the angle of the prism is 5° and the prism is made of a material of refractive index 1.5, the angle of incidence is (a) 7.5°. (b) 5°. (c) 15°. (d) 2.5°.

In an ac circuit, the current is given by i = 4 sin (100 πt + 30º) ampere. The current becomes maximum first time (after t = 0) at t equal to :

On the valid performance of the contractual obligations by the parties, the contract ………(a) Is discharged (b) Become enforceable (c) Becomes void (d) Becomes legal

Which of the following persons can perform the contract?(a) Promisor alone (b) Legal representatives of promisor (c) Agent of the promisor (d) All the above

What is a Valid tender?

Explain rules relating to place of performance of promise.

Who is a Joint Promisors?

By whom must contracts be performed?

Who is a Legal Representative?

If i and r be the angles of incidence and refraction respectively, when the light ray travels from glass to air, then A) i = rB) i &gt;r C) i &lt; r D) none

Funds required for purchasing current assets is an example for …………(a) Fixed Capital Requirement (b) Ploughing Back of Profits (c) Working Capital Requirement (d) Lease Financing

State two advantages of ploughing back profits?

What is retained profit or ploughing back profits?

Two capacitor c1 = 2μf and c2 = 4μf are connected in series and a potential difference (p.d) of 1200 v is applied across it the potential difference across 2μf will beA) 400 V B) 600 V C) 800 V D) 900 V

64 identical drops each of capacity 5μF combine to form a big drop. Capacity of the big drop will A) 4μF B) 25μF C) 20μF D) 164 μF

64 identical drops each of capacity 5μF combine to form a big drop. Capacity of the big drop will beA. 4μF B. 25μF C. 20μF D. 164μF

Which one is the internal source? (a) Retained earnings (b) Shares (c) Debentures (d) Public deposits

The average profit earned by the firm is Rs. 80,000 which includes under valuation of stock an average basis the capital invested in the business and normal rate of return is 8%. Calculate the goodwill of the firm on the basis of times the super profit.

Funds required for purchasing current assets is an example of (a) Fixed capital requirement (b) Ploughing back of profits (c) Working capital requirement (d) Lease financing

The capacitance of parallel plate capacitor........by introduction of dielectric between the plates of the capacitor A) Increases B) Decreases C) Remain same D) 0

The electric potential in equatorial position of an electric dipole is

At constant Potential difference, the resistance of any electric circuit is halved; the value of heat produced will beA) Half B) Doubled C) Four times D) Same

If L be the inductance, R resistance and C be the capacitance of a capacitor, then dimensional formulae of L/R and RC are

The term ‘redeemable’ is used for (a) Preference shares (b) Commercial paper (c) Equity shares (d) Public deposits

The term‘redeemable’ is used for (a) Preference shares (b) Commercial paper (c) Equity shares (d) Public deposits

Redeemable preference shares can be(A) Redeemed before 20 years(B) Redeemed after 20 years(C) Only partly redeemed after 20 years(D) Both (A) and (B)

List of the basic units in the SI units.

Write the number of significant figures in each of the following measurements1. 1.67 × 10-27 kg2. 0.270 cm

Name the SI unit of weight.

What are the Advantages of SI units?

Write a note on the SI system.

Show that 1 Joule = 107erg by the method of dimension.

Why is the speed of whirl wind in a tornado so high?

A dimensionally correct equation need not actually be a correct equation but dimensionally incorrect equation is necessarily wrong. Justify.

Why the speed of whirl wind in a Tornado is alarmingly high?

What is drop is potential energy if M1 goes down by d1∆θ and M2 goes up by d2∆θ in case of two bodies of masses M1 and M2 sitting on a seesaw and balancing each other initially?

Check whether the given equation \(F.s=\frac{1}{2}mv^2-\frac{1}{2}mu^2\) is dimensionally correct, or not where, m is mass of the body, v is its final velocity, u is its initial velocity, F is applied force and s is distance covered.

If i and r be the angles of incidence and refraction respectively, when the light ray travels from glass to air, then A) i = rB) i >r C) i < r D) none