Latest Posts

The plot given below is of the average power delivered to an LRC circuit versus frequency. The quality factor of the circuit is:

a) 5.0 b) 2.0 c) 2.5 d) 0.4 Answer: b) 2.0 Solution: From the graph, Resonating frequency (at which the peak... View Article

In the figure shown, a small ball hits obliquely a smooth and horizontal surface with speed u whose x and y components are indicated. If the coefficient of restitution is 1/2 then its x and y components v_x and v_y just after a collision are respectively

a) 4 m/s, 1 m/s b) 2 m/s, 1 m/s c) 2 m/s, 2 m/s d) 4 m/s, 2... View Article

AB and CD are a long straight conductor, distance d apart, carrying a current I. The magnetic field at the
the midpoint of BC is

a) \(\begin{array}{l}\frac{-\mu _{0}I}{2\pi d}\hat{k}\end{array} \) b) \(\begin{array}{l}\frac{-\mu _{0}I}{\pi d}\hat{k}\end{array} \) c) \(\begin{array}{l}\frac{-\mu _{0}I}{4\pi d}\hat{k}\end{array} \) d) \(\begin{array}{l}\frac{-\mu _{0}I}{8\pi d}\hat{k}\end{array} \) Answer: b) \(\begin{array}{l}\frac{-\mu _{0}I}{\pi d}\hat{k}\end{array} \)... View Article

Two α – particles have the ratio of their velocities as 3:2 on entering the field. If they move in different circular paths, then the ratio of the radii of their paths is:

a) 2:3 b) 3:2 c) 9: 4 d) 4:9 Answer: b) 3:2 Solution: Centripetal force = Magnetic force Fc = Fm... View Article

In an inertial frame of reference, the magnetic force on a moving charged particle is [latex]vec{F}[/latex]. Its value in another inertial frame of reference will be ______.

a) remained same b) changed due to change in the amount of charge c) changed due to change in velocity of... View Article

A vibratory motion is represented by x=2Acosωt+Acos(ωt+π/2)+Acos(ωt+π)+(A/2)cos(ωt+3π/2). The resultant amplitude of the motion is

a)9A/2 b)√5A/2 c)5A/2 d) 2A Answer:b)√5A/2 Solution: x=2Acosωt+Acos(ωt+π/2)+Acos(ωt+π)+(A/2)cos(ωt+3π/2) x = 2Acosωt – Asinωt – Acosωt + (A/2)sinωt = Acosωt- (A/2)sinωt Resultant... View Article

The magnetic flux threading a metal ring varies with time t according to Φ_B = 3(at³ -bt²) T-m² with a = 2.00 s^-3 and b = 6.00 s^-2.The resistance of the ring is 3.0 Ω. Determine the maximum current induced in the ring during the interval from t = 0 to t = 2.0 s.

a)12 A b) 3 A c) 6 A d) 8 A Answer:6 A Solution: Given, ΦB = 3(at3 -bt2) Therefore,... View Article

Find the maximum speed with which a car can turn on a bend without skidding if the radius of the bend is 20 m and the coefficient of friction between the road and the tyres is 0.4.

Answer: 4√5 m/s Solution: Given, Radius, R = 20 m Coefficient of friction, μs = 0.4 v = √μsRg = √0.4 x 20 x... View Article

HCF of 100 and 4423 is

The HCF of 100 and 4423 is 1. Explanation: The factors of 100 are 1, 2, 4, 5, 10, 20,... View Article

If (107)×8 = (y)×2, find the value of y.

Given: (107)×8 = (y)×2 Thus, 2y = 856 ⇒ y = 856/2 ⇒ y = 428. Hence, the value of... View Article

Convert 37 into binary.

37 in binary is 1001012. Step 1: Divide 37 by 2. Now, use the quotient obtained in this step as... View Article

What is A∩B means in probability?

In Probability, the symbol “∩” represents the intersection. A intersection B defines the elements that are common in both sets... View Article

How to find the square root of 140?

The square root of 140 is approximately equal to 11.832. To find the square root of a number, follow the... View Article

A large heavy sphere and a small light sphere are dropped together onto a flat surface from a height h. The radius of spheres is much smaller than height h. The large sphere collides with the surface with velocity Vo and immediately thereafter with the small sphere. The spheres are dropped so that all motion is vertical before the second collision, and the small sphere hits the larger sphere at an angles from its uppermost point as shown in the diagram. All collisions are perfectly elastic and there is no surface friction between the spheres. The angle made by the velocity vector of the small sphere with the vertical just after the second collision in the frame of the large sphere.

a) \(\begin{array}{l}\alpha \end{array} \) b) \(\begin{array}{l}2\alpha \end{array} \) c) Zero d) \(\begin{array}{l}\frac{3\alpha}{2}\end{array} \) Solution: b) 2\alpha Explanation:\(\begin{array}{l}e=1=\frac{V+V_{0}cos\alpha}{V_{0}cos\alpha+V_{0}cos\alpha}\end{array} \) \(\begin{array}{l}V=V_{0}cos\alpha\end{array} \)... View Article

The phase difference between current and voltage in an AC circuit is π/4 radian. If the frequency of AC is 50Hz, then the phase difference is equivalent to the time difference?

Solution: The phase difference between current and voltage is given by \(\begin{array}{l}\phi=\frac{\pi}{4}\end{array} \), f=50 Hz \(\begin{array}{l}f=\frac{1}{T}=\frac{1}{50} = 0.02s\end{array} \) For... View Article

A truck and a car moving with the same kinetic energy are brought to rest by the application of brakes which provides equal retarding forces. Which of them will come to rest in a shorter distance?

a) The truck b) The car c) Both will travel the same distance before coming to rest d) Cannot be... View Article

Assertion: A body can have acceleration even if its velocity is zero at a given instant of time. Reason: A body is numerically at rest when it reverses its direction.

a) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion. b) Both Assertion and Reason... View Article

Energy dissipated in the LCR circuit in :

a) R only b) L only c) C only d) All the above option Solution: a) R only Explanation: In... View Article

A flood light is covered with a filter that transmits red light. The electric field of the emerging beam is represented by a sinusoidal plane wave [latex]E_{x}=36 sin (1.2010^{7}z+610^{15}t)[/latex] V/m. What will be the average intensity of the beam?

<p><strong>Solution:</strong> Average intensity is given by the formula: \(\begin{array}{l}I=\frac{\epsilon_{0}cE_{rms}^{2}}{2}\end{array} \) \(\begin{array}{l}I=\frac{8.85*3*36*36*10^{-4}}{2} = 1.72 \frac{W}{m^{2}}\end{array} \)

An rlc circuit is driven by a sinusoidal EMF with angular frequency. If angular frequency is increased without changing the amplitude of the EMF , the current amplitude increases, it means?

a. \(\begin{array}{l}\omega L> \frac{1}{\omega C}\end{array} \) b. \(\begin{array}{l}\omega L< \frac{1}{\omega C}\end{array} \) c. \(\begin{array}{l}\omega L= \frac{1}{\omega C}\end{array} \) d. None... View Article

«
1
…
706
707
708
709
710
…
5,472
»