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Find the potential drop across 4μF capacitor and 6Ω resistor in figure.

a) 0,0 b) 0, 3V c) 0, 2V d) 2V, 0 Answer: d) 2V, 0 Solution: A fully charged capacitor draws no current, hence no current flows... View Article

In a transformer, the output current and voltage are respectively 4 A and 20V. If the ratio of number of turns in the primary to secondary is 2:1 what is the input current and voltage?

Answer:2 A Solution: (Ns/Np) = (Ip/Is) = (Vs/Vp) Vp = Vi = (Np/Ns) x Vs = (2/1) x 20 = 40 V Ip = (Ns/Np) x Is = (1/2) x 4 = 2 A... View Article

In the circuit shown in figure, the current measured by the ammeter is

a) 1 A b) 2 A c) 3 A d) Zero Answer: c) 3 A Solution: From the graph √(100 - 60)2 + VR2 = Vnet √(40)2 + VR2 = Vnet VR2 = (30)2 VR =... View Article

If the angular velocity of a disc depends on an angle rotated as ω=(θ²+θ), then its angular acceleration at θ=1 rad is

a) 3 rad/s2 b) 6 rad/s2 c) 2 rad/s2 d) 9 rad/s2 Answer: a) 3 rad/s2 Solution: Given, ω=(θ2+θ) Angular... View Article

A magnetic compass needle oscillates 30 times per minute at a place where the dip is 45°, and 40 times per minute where the dip is 30º. If B1 and B2 are respectively the total magnetic field due to the earth at the two places, then the ratio B₁/ B₂ is best given by:

(1) 1.8 (2) 2.2 (3) 0.7 (4) 3.6 Answer: (3) 0.7 Solution: τ = -mBsinθ τ... View Article

The magnetic flux linked with a coil of N turns of the area of cross-section A held with its plane parallel to the field B is

a) NAB/2 b) NAB c) NAB/4 d) 0 Answer: d) 0 Solution: Φ = NBAcosθ = NBAcos 900 = 0... View Article

The V-I graph for a conductor at temperature T₁ and T₂ are as shown in fig. The term (T₂−T₁) is proportional to

a) cos2θ b) sinθ c) cot2θ d) tanθ Answer: c) cot2θ Solution: T2 - T1 = tan(90 - θ) - tan θ = cot θ - tan θ = (cos θ/sin θ) -... View Article

A circular loop is kept in that vertical plane which contains the north-south direction. It carries a current that is towards north at the topmost point. Let A be a point on the axis of the circle to the east of it and B be a point on this axis to the west of it. The magnetic field due to the loop

a) is towards east at A and towards west at B b) is towards west at A and towards east at B c) is towards east at both A and B d) is towards... View Article

An observer A and a charge Q are fixed in a stationary frame F₁. An observer B is fixed in a frame F₂, which is moving with respect to F₁

(a) Both A and B will observe electric fields. (b) Both A and B will observe magnetic fields. (c) Neither A nor B will observe magnetic fields.... View Article

A ray of light travelling along the line x+y=1 is inclined on the x-axis and after refraction it enters the other side of the x-axis by turning 15⁰ away from the x-axis. The equation of the line along which the refraction ray travels is

a) √3y-x+1 = 0 b) √3y+x+1 = 0 c) √3y+x-1 = 0 d) None of these Answer: d) None of these Solution: Slope = tan (1800-600) = tan 1200 = -√3... View Article

Three blocks are connected by strings as shown in the figure and pulled by a force F = 60N. If m_A =10 kg, m_B =20 kg, and m_C=30 kg, then:

a) acceleration of the system is 2m/s2 b) T1 = 10 N c) T2 = 30 N d) T1 = 20 N and T2 = 40 N Answer: b and c Solution: Acceleration of the... View Article

A current of 10 A flows around a closed path in a circuit that is in the horizontal plane as shown in the figure. The circuit consists of eight alternating areas of radii r₁=0.08m and r₂=0.12m. Each arc subtends the same angle at the centre.

(a) Find the magnetic field produced by this circuit at the centre. (b) An infinitely long straight wire carrying of 10 A is passing through the... View Article

Convert 1 minute to milliseconds.

We know that the minute and milliseconds are the units of time. The symbol to represent minute is “min” and milliseconds is... View Article

How to find the angle between vector and x axis?

The angle between the vector and the x-axis can be determined using methods such as dot product of two vectors, and the cross product of two... View Article

The P.I. of (3D^2+D−14)y=13e^2x is:

Given equation: (3D2+D−14)y=13e2x Thus, the P. I of (3D2+D−14)y=13e2x is: P.I = [1/(3D2+D−14)] . (13e2x) Now, replace... View Article

Can a determinant be calculated for a 5×4 matrix?

In Mathematics, a determinant is defined as the scalar value, which is the function of the entries in the square matrix. If A is the given... View Article

What is meant by transformations of functions?

In Mathematics, the transformation of function represents the change of one function to the other function. The four types of transformations in... View Article

The bar graph given alongside shows the amount of wheat purchased by the government during the year 1998 – 2002. Read the bar graph and write down your observations. In which year was (i) the wheat production maximum (ii) the wheat production minimum?

Bar Graph: (i) Wheat Production - Maximum: From the given bar graph, the highest bar is in the year 2002. Hence, the wheat production was... View Article

The area bounded by the curve y = cos x, the x-axis and the ordinates x=0 and x=2pi

The area bounded by the curve y = cos x, the x-axis and the ordinated x=0 and x=2 is given by Area bounded = = (since 0 ≤ x < /2... View Article

Let f(x) be a polynomial satisfying limit x tends to infinity [x^2f(x)/(2x^5 + 3)]=6, also f(1)=3, f(3)=7, and f(5)=11, then find the value of [f(6) + 5f(4)]/29.

Given, then, f(x) is a polynomial function of degree 3 [ If the degree of f(x) < 3, the limit will tend to zero. If the degree of f(x)... View Article