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Kinetic Energy and momentum

Ahsan asks:

“if kinetic energy of a body is increased to 100%
than what will be the momentum of the body?”



Kinetic Energy is increased by 100% means that the KE is doubled (1+1=2)

From the equation

If E is doubled, P will become √2 times its original value

A Problem from gravitation

Soumya asked:

“A body of mass 5kg is taken on equitorial plane.
But due to some change earth’s diurnal motion, its
weight has become zero. What will be the length of
day now?”


(The question will be answered soon. Visitors can send their responses as comments to this post)

Problem from Vectors and Kinematics

James Allen asks:

“Over the course of about six weeks in 1992, Aki Matusushima, from Japan, rode a unicycle more than 3000 mi across the United States. Suppose Matsushima is riding through a city. If he travels 250.0 m east oone street, then turns counterclockwise through a 120 degree angle and proceed 125.0 m northwest along a diagonal street, what is his net displacement?”


(The question will be answered soon. Visitors can send their response and comment to this post)

Doppler Effect

Hasan asks:

“What is Doppler Effect?”



Doppler Effect is the apparent change in frequency of a wave due to the relative motion between the source and the listener.

(Please come back soon for more details with figures and videos)

Doubts related to Electric Dipole

Ela asks:

  1. Magnitude and direction of dipole field depends not only on distance r from centre of dipole,but also on the angle between the position vector rand the dipole moment p how?
  2. How can centres of positive and negative charge lie on same place and if both have same charge they should become neutral?


1. The electric field at a point due to a dipole is given by

Which clearly explains the answer to your question

2. Centre of positive charge means the centre of mass of all the positive charged particles and similarly for the negative charge. If the atom or molecule is symmetric, the two centres of charge will coincide; just like the centre of mass of two concentric hollow spheres. The charges are not at the same point, but their centres of mass coincide. If they do not coincide, it will give rise to an electric dipole or a polar molecule.

What is GPR in Physics?

Maurice Udung Etor asked:

What is GPR in Physics?


GPR means Ground Penetrating RADAR

Ground penetrating radar locates almost anything underground. Ground penetrating radar makes an underground cross-sectional, two-dimensional image of the soils and subsurface features.

Multiple lines of data systematically collected over an area may be used to construct three-dimensional or tomographic images. Data may be presented as three-dimensional blocks, or as horizontal or vertical slices. Horizontal slices (known as “depth slices” or “time slices”) are essentially planview maps isolating specific depths.

Find more details at:

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