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Asked by Anurag Verma

Jul 28, 2014

A hollow metal sphere of radius 5 cm is charged such that the potential on its surface is 10 V. What is the potential at the centre of the sphere?

Answer.

In the case of a hollow metal sphere, the electric field inside the shell is zero. This means that the potential inside the shell is constant. Therefore the pot...

In the case of a hollow metal sphere, the electric field inside the shell is zero. This means that the potential inside the shell is constant. Therefore the pot...

Asked by Adarsh Nair

Feb 23, 2015

What is a ballistic galvanometer and what is its principle?

Answer.

A ballistic galvanometer is a galvanometer specially designed to measure the quantity of charge displaced in a current of short duration (such as in the chargin...

A ballistic galvanometer is a galvanometer specially designed to measure the quantity of charge displaced in a current of short duration (such as in the chargin...

Asked by Amarnathreddy M

Feb 1, 2014

Distinguish between self-induction and mutual induction.

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Asked by Anubhav Singh

Dec 23, 2014

The angular momentum of an electron in a hydrogen atom is proportional to (where r is radius of orbit ):

a) 1**/**r^{1/2}

b) 1**/**r

c) r^{1/2}

d) r^{2}

a) 1

b) 1

c) r

d) r

Answer.

Radius of the nth orbit r_{n} ∝ n^{2}/Z ⇒ n &#...

Asked by Altaf Hussain Shaikh Ahmed

Mar 19, 2015

Give construction and working of meter bridge.

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Asked by Vaibhav Gumber

Jun 1, 2015

An infinite line charge produces a field of 9 X 10^{4 }N/C at a distance of 2 cm. Calculate the linear charge density.

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Asked by Misha Jain

Aug 15, 2014

Equation of alternating current is given by I = 10√2 sin(100πt + π/6). If the time taken by current to reach the root mean square value from t=0 is t', then what is the value of t'?

Answer.

Instantaneous value of current I = 10√...

Instantaneous value of current I = 10√...

Asked by Arunima Ajan

Nov 21, 2014

A convex lens has a focal length f in air. What happens to the focal length of the lens, if it is immersed in water of refractive index 1.33?

Asked by Harsha

Apr 12, 2014

a proton is placed in a uniform electric field directed along positive x axis .in which direction will it tend to move?

Answer.

The proton will move in the direction of the electric field that is the +ve X-axis to –ve X axis. proton moves in direction of the elec...

The proton will move in the direction of the electric field that is the +ve X-axis to –ve X axis. proton moves in direction of the elec...

Asked by Misha Jain

Aug 15, 2014

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

Answer.

Phase difference ϕ = π/4 radian

Frequency f = 50 Hz

Time difference Δt = ϕ/(2πf)

= π/(4 x 2π x 50)

= 1/(400)

= 0.0025 s

...

Phase difference ϕ = π/4 radian

Frequency f = 50 Hz

Time difference Δt = ϕ/(2πf)

= π/(4 x 2π x 50)

= 1/(400)

= 0.0025 s

...