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How do you calculate the number of sigma pi bonds in CH3−CH=CH−C≡CH ?

The given compound is pent-3 -en-1 -yne. The chemical formula of the compound is C5H6 and molecular weight is 66g . The compound is composed... View Article

Among the following series of transition of metal ions, the one where all metal ions have 3d2 electronic configuration is: A. Ti+,V4+,Cr6+,Mn7+ B. Ti4+,V3+,Cr2+,Mn3+ C. Ti2+,V3+,Cr4+,Mn5+ D. Ti3+,V2+,Cr3+,Mn4+

Answer: (c) C. Ti2+,V3+,Cr4+,Mn5+ The charge on the specified metal atoms must be checked and matched with the electrical configuration of... View Article

The spring extends by x on loading, then energy stored by the spring is (if T is the tension in spring and k spring constant).

When a weight of W is put to one end of the spring, we may infer that the real length of the spring is L, which is stretched by a length of x.... View Article

When a horse pulls a cart, the force that helps the horse to move forward is the force exerted by, A. the cart on the horse B. the ground on the horse C. the ground on the cart D. the horse on the ground

Answer: B. the ground on the horse The horse's forward motion is in the forward direction. Reaction forces are always found in pairs, as we... View Article

An object is placed at a distance of 1.5 m from a screen and a convex lens is interposed between them. The magnification produced is 4. The focal length of the lens is then

The distance between the convex lens or a concave mirror and the focal point of a lens or mirror is called the focal length. It is the point... View Article

A force acts on a 2 Kg object so that its position is given as a function of times as x=3t²+5. What is the work done by this force in the first 5 seconds?

Given parameters are The mass of an object = 2Kg The function of time: x=3t2+5 Force: A force is a push or pull upon an object resulting from... View Article

A ball is dropped from height h on a horizontal floor. If it loses 60% of its energy on hitting the floor then upto which it will rise after first rebounce is?

60 percent of the energy is lost. Then use energy conservation as follows: mgh=mgh1+(60/100)mgh Here, m is the mass of the ball, h is the... View Article

Two concentric coplanar circular loops made of wire, with resistance per unit length 10⁻⁴Ωm⁻¹ have diameters 0.2 m and 2 m. A time varying potential difference (4+2.5t) is applied to the larger loop. Calculate the current in the smaller loop.

The magnetic field at the centre O due to the current in the larger loop is B=μ0I/2R If r is the resistance per unit length, then I= potential... View Article

What is the force of attraction between the plates of a parallel plate capacitor?

Electric field by any one plate is given by, E = σ2/ϵ0 ...(1) Where, E is the electric field σ is the area density of charge ϵ0 is the... View Article

A long solenoid of diameter 0.1m has 2×10⁴ turns per meter. At the centre of the solenoid, a coil of 100 turns and radius 0.01m is placed with its axis coinciding with the solenoid axis. The current in the solenoid reduces at a constant rate to 0A from 4A in 0.05s . If the resistance of the coil is 10π²Ω , the total charge flowing through the coil during this time is

The inner coil will generate emf due to the flowing current in the long solenoid. Current will pass through the inner coil since it has some... View Article

A parachutist after bailing out falls 50m without friction. When the parachute opens, it decelerates at 2ms⁻². He reaches the ground with speed 3ms⁻². At what height did he bail out?

The fundamental concepts of motion of any object are described by the basic equations of motion. These equations control an object's motion in... View Article

The amplitude of a particle executing SHM about O is 10cm. Then(A) When the K.E. is 0.64 of its max. K.E. its displacement is 6cm from O. (B) When the displacement is 5cm from O its K.E.is 0.75 of its max. P.E. (C) Its total energy at any point is equal to its maximum K.E. (D) Its velocity is half the maximum velocity when its displacement is half the maximum displacement.

We know that in SHM, total mechanical energy is conserved: ME = KE + PE ME = KEmax ME = PEmax Now,... View Article

An engine is moving on a circular path of radius 100 metre with a speed of 20 metre per second. The frequency observed by an observer standing stationary at the centre of circular path when the engine blows a whistle of frequency 500 Hz is

answer (c) There is no doppler effect, since the relative velocity of the engine is perpendicular to the observer. As a result, the frequency... View Article

In the circuit diagram, find the current through the Zener diode given below

Since the resistance R2 and the Zener diodes are linked in parallel, the voltage across them is equal, resulting in a potential difference of 10... View Article

A constant force acts on an object of mass 5 Kg for a duration of 2 seconds. It increases the objects v=u+atvelocity from 3m/s to 7m/s . Find the magnitude of the applied force. Now if the tax were applied for a duration of 5seconds, what would be the final velocity of the object ?<

The initial and final velocity of the items are given, however we must assume that initial and final velocity. We must calculate the object's... View Article

A bead of mass m is attached to one end of the spring of natural length R and spring constant K=(√3+1)mg/R. The other end of the spring is fixed at point A on a smooth vertical ring of radius R as shown in fig. The normal reaction at B just after it is released to move is

In ΔAOM and ΔBOM, AM=BM=Rcos30⇒AM=BM = √3/2R The spring is stretched and hence its length is extended. Given, R is the original length of the... View Article

A rectangular loop of sides 10cm and 5cm carrying a current I of 12A is placed in different orientations as shown in the figure below: If there is a uniform magnetic field of 0.3T in the positive z-direction, in which orientations the loop would be in (A) Stable equilibrium and (B) Unstable equilibrium?

Only torque acts on a current carrying loop because the magnetic field B is uniform. The vector product of the magnetic moment and the magnetic... View Article

M	T	W	T	F	S	S
	1	2	3	4	5	6
7	8	9	10	11	12	13
14	15	16	17	18	19	20
21	22	23	24	25	26	27
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