Recent content by lingling

Homework Statement This is a question about turning effect on a current-carrying coil lying between the poles of a magnet. Please refer to the following link: http://img11.picsplace.to/img.php?file=img10/22/N1_000.gif On the textbook, it is stated the turning effect on the coil can be...

How can I know the kinetic energy of the boy without knowing the speed? My stupid thought was that to use the increase in gravitational potential energy of the boy but I can't get the answer. Why?

Homework Statement A boy of 60 kgtakes 5 s to run up the slope in the diagram. (Please refer to the attachment) What is his average kinetic energy? Homework Equations The Attempt at a Solution I don't know the meaning of 'average' kinetic energy. Is this mean kinetic energy per...

Homework Statement A bob is hung by a light string and and is pushed sideways. A peg of wood is placed vertically below the point of suspension of the string to hinder the motion of string as shown in the figure below: (please refer to the attachment) The bob is released. Which of the...

Ah... I've got it! Thanks a lot!

Homework Statement A stone of mass 2 kg is projected horizontally with a speed of 20 m/s from a cliff which is 15 m above the ground. Find the energy possessed by the stone just before touching the ground. A. 400J B. 500J C. 600J D. 700J Homework Equations The Attempt at a...

Homework Statement Refer to the uploaded file, Which of the following statements is/are correct? (1) The length of each tape represents the average velocity within the time interval. (2) The width of the tape represents the constant time interval. (3) Joining the centres of the tops of...

What is the meaning of a ' transverse magnetic field '? I 've seen it once in a question. It asked 'when a beam of alpha particles enter a transverse magnetic field, ...' I guessed it means the direction of the beam traveling is perpendicular to the direction of magnetic field. Is this...

wow... silly me. Thank you!

Argee! That's why i don't know how to solve this question.

Homework Statement Which of the following forces is responsible for the scattering of an alpha particle by a gold atom in the Geiger-Marsden experiment? A. electrostatic force between the alpha particle and the electrons of the gold atom B. Electrostatic force between the alpha...

Homework Statement which of the following mass ration is ture? Mass of alpha-particles: mass of neutrons : mass of gamma- rays equal to A. 4 : 1 : 0 B. 4 : 0 : 1 C. 1 : 1 : 1 D. 1 : 1 :0 Homework Equations nil The Attempt at a Solution I thought it's D but the...

Homework Statement 1. Which of the following statements is / are not correct? (1) In fission, two large fragments of equal masses are produced from a nuclide. (2) Natually occurring elements perform fission spontaneously. (3) 2 H2O --> 2H2 + O2 involves nuclear fission. Homework...

Homework Statement Which of the following reactions will release large amount of energy (1) Nuclear fusion (2) alpha - decay (3) Nuclear fission (4) gamma - decay two of the options are: B (1) and (3) only D (1), (2), (3), (4) Homework Equations none The Attempt at a...

I still cannot understand. Is there any simpler approach?