The correct statement regarding the electric field due to static charges is that it is conservative and field lines do not form closed loops.
An electric field is said to be conservative if the work done by the electric field on a test charge is independent of the path taken and depends only on the initial and final positions. This implies that the work done around any closed path is zero, a property of a conservative field. Mathematically, for a conservative field, we have:
\(∮C E · dl = 0\)
where ∮C indicates the integral around a closed path and E is the electric field. Therefore, the electric field created by static charges is conservative.
Additionally, the electric field lines of static charges start at positive charges and end at negative charges, without forming closed loops. This is in contrast to the magnetic field lines, which do form closed loops. Therefore, the statement that the electric field is conservative and field lines do not form closed loops is correct.
A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:
(i)} Express the distance \( y \) between the wall and foot of the ladder in terms of \( h \) and height \( x \) on the wall at a certain instant. Also, write an expression in terms of \( h \) and \( x \) for the area \( A \) of the right triangle, as seen from the side by an observer.
निम्नलिखित गद्यांश की सप्रसंग व्याख्या कीजिए :
‘‘पुर्ज़े खोलकर फिर ठीक करना उतना कठिन काम नहीं है, लोग सीखते भी हैं, सिखाते भी हैं, अनाड़ी के हाथ में चाहे घड़ी मत दो पर जो घड़ीसाज़ी का इम्तहान पास कर आया है उसे तो देखने दो । साथ ही यह भी समझा दो कि आपको स्वयं घड़ी देखना, साफ़ करना और सुधारना आता है कि नहीं । हमें तो धोखा होता है कि परदादा की घड़ी जेब में डाले फिरते हो, वह बंद हो गई है, तुम्हें न चाबी देना आता है न पुर्ज़े सुधारना तो भी दूसरों को हाथ नहीं लगाने देते इत्यादि ।’’