Question Number 181053 by Acem last updated on 22/Nov/22 $${An}\:{open}\:{pipe}\:{of}\:{r}_{{o}} =\:\mathrm{10}\:{Cm},\:\ell=\:\mathrm{3}{m}\:{has}\:{an}\:{outer} \\ $$$$\:{layer}\:{of}\:{ice}\:{that}\:{is}\:{melting}\:{at}\:{the}\:{rate}\:{of}\:\mathrm{2}\pi\:{Cm}^{\mathrm{3}} \\ $$$$\:{per}\:{minute}\:{with}\:{thickness}\:{of}\:\mathrm{20}\:{mm}.\:{How}\:{many} \\ $$$$\:{days}\:{untill}\:{all}\:{the}\:{ice}\:{melts}?\:{and}\:{how}\:{fast}\:{is}\:{the} \\ $$$$\:{thickness}\:{of}\:{the}\:{ice}\:{decreasing}\:{per}\:{hour}? \\ $$ Answered by Acem last…
Question Number 181052 by Acem last updated on 20/Nov/22 Commented by Acem last updated on 20/Nov/22 $$\ast\:{When}\:{the}\:{car}\:{is}\:\mathrm{6}\:{Km}\:{from}\:{A} \\ $$ Commented by mr W last updated…
Question Number 49966 by Necxx last updated on 12/Dec/18 $${A}\:{conveyor}\:{belt}\:{is}\:{driven}\:{at}\:{velocity} \\ $$$${v}\:{by}\:{a}\:{motor}.{Sand}\:{drops}\:{vertically} \\ $$$${on}\:{to}\:{the}\:{belt}\:{at}\:{a}\:{rate}\:{of}\:\boldsymbol{{m}}{kg}/{s}. \\ $$$${What}\:{is}\:{the}\:{additional}\:{power} \\ $$$${needed}\:{to}\:{keep}\:{the}\:{conveyor}\:{belt} \\ $$$${moving}\:{at}\:{a}\:{steady}\:{speed}\:{when} \\ $$$${the}\:{sand}\:{starts}\:{to}\:{fall}\:{on}\:{it}? \\ $$$$\left.{a}\left.\right)\left.\frac{\mathrm{1}}{\mathrm{2}}\left.{mv}\:{b}\right){mv}\:{c}\right)\frac{\mathrm{1}}{\mathrm{2}}{mv}^{\mathrm{2}} \:{d}\right){mv}^{\mathrm{2}}…
Question Number 49583 by ajfour last updated on 08/Dec/18 Commented by ajfour last updated on 08/Dec/18 $${If}\:{the}\:{paraboloid}\:{cup}\:{is}\:{absolutely} \\ $$$${slippery},\:{find}\:{fraction}\:{of}\:{stick} \\ $$$${length}\:{outside}\:{the}\:{cup}. \\ $$ Commented by…
Question Number 49559 by Rio Michael last updated on 07/Dec/18 Commented by Rio Michael last updated on 07/Dec/18 $${The}\:{figure}\:{below}\:{shows}\:{an}\:{object}\:{of}\:{mass}\:\mathrm{60}{kg}\:{pulled}\:{up} \\ $$$${by}\:{an}\:{effort}\:{of}\:\mathrm{4000}{J}\:{through}\:{an}\:{inclined}\:{plane}\:\mathrm{30}°\:{to}\:{the}\: \\ $$$${horizontal}. \\ $$$$\left.{a}\right)\:{Sketch}\:{the}\:{diagram}\:{showing}\:{all}\:{forces}\:{acting}\:{on}\:{the}\:{object}…
Question Number 49491 by Necxx last updated on 07/Dec/18 $${A}\:{rocket}\:{of}\:{mass}\:\mathrm{1000}{kg}\:{containing} \\ $$$${a}\:\:{propellant}\:{gas}\:{of}\:\mathrm{3000}{kg}\:{is}\:{to} \\ $$$${be}\:{launched}\:{vertically}.{If}\:{the}\:{fuel} \\ $$$${is}\:{consumed}\:{at}\:{a}\:{steady}\:{rate}\:{of} \\ $$$$\mathrm{60}{kg}/{s}.{Calculate}\:{the}\:{least}\:{velocith} \\ $$$${of}\:{the}\:{exhaust}\:{gases}\:{if}\:{the}\:{rocket} \\ $$$${and}\:{the}\:{content}\:{will}\:{just}\:{lift}\:{off} \\ $$$${the}\:{launching}\:{pad}\:{immediately} \\…
Question Number 114850 by Rio Michael last updated on 21/Sep/20 $$\mathrm{a}\:\mathrm{man}\:\mathrm{hits}\:\mathrm{a}\:\mathrm{golf}\:\mathrm{ball}\:\mathrm{at}\:\mathrm{the}\:\mathrm{top}\:\mathrm{of}\:\mathrm{a}\:\mathrm{cliff} \\ $$$$\mathrm{which}\:\mathrm{is}\:\mathrm{40}.\mathrm{0}\:\mathrm{m}\:\mathrm{high}.\:\mathrm{given}\:\mathrm{that}\:\mathrm{the} \\ $$$$\mathrm{ball}\:\mathrm{falls}\:\mathrm{into}\:\mathrm{a}\:\mathrm{water}\:\mathrm{down}\:\mathrm{cliff}\:\mathrm{and}\:\mathrm{he} \\ $$$$\mathrm{hears}\:\mathrm{the}\:\mathrm{sound}\:\mathrm{3}\:\mathrm{s}\:\mathrm{after}\:\mathrm{he}\:\mathrm{hit}\:\mathrm{the}\:\mathrm{ball}. \\ $$$$\mathrm{what}\:\mathrm{is}\:\mathrm{the}\:\mathrm{initial}\:\mathrm{speed}\:\mathrm{of}\:\mathrm{the}\:\mathrm{ball}.\:\mathrm{take} \\ $$$$\mathrm{the}\:\mathrm{speed}\:\mathrm{of}\:\mathrm{sound}\:\mathrm{in}\:\mathrm{air}\:\mathrm{as}\:\mathrm{343}\:\mathrm{m}/\mathrm{s}.\:\mathrm{neglect} \\ $$$$\mathrm{air}\:\mathrm{resistance}. \\ $$…
Question Number 49096 by peter frank last updated on 02/Dec/18 Answered by tanmay.chaudhury50@gmail.com last updated on 02/Dec/18 $$\left.{a}\right){velocity}\:{of}\:{man}\:{w}.{r}.{t}\:{ground}\:={V}_{{G}} ^{{m}} ={V}_{{G}} ^{{B}} +{V}_{{B}} ^{{m}} \\ $$$${if}\:{the}\:{was}\:{seated}\:{in}\:{chair}\:{or}\:{standing}\:…
Question Number 49097 by peter frank last updated on 02/Dec/18 Answered by tanmay.chaudhury50@gmail.com last updated on 02/Dec/18 $${T}=\mathrm{3}×\mathrm{10}=\mathrm{30}{N} \\ $$$${Normal}\:{reaction}=\mathrm{5}×\mathrm{10}=\mathrm{50}{N} \\ $$$${limiting}\:{friction}\:{f}_{{L}} =\mathrm{0}.\mathrm{55}×\mathrm{50}=\mathrm{27}.\mathrm{5}{N} \\ $$$${kinetic}\:{friction}\:{f}_{{k}}…
Question Number 49093 by peter frank last updated on 02/Dec/18 Answered by tanmay.chaudhury50@gmail.com last updated on 02/Dec/18 $$\left.\mathrm{12}\right){Normal}\:{reaction}\:{N}=\mathrm{5}×\mathrm{10}=\mathrm{50}{N} \\ $$$${limiting}\:{friction}\:{f}_{{L}} =\mathrm{0}.\mathrm{42}×\mathrm{50}=\mathrm{21}{N} \\ $$$${kinetic}\:{friction}\:{f}_{{k}} =\mathrm{0}.\mathrm{15}×\mathrm{50}=\mathrm{7}.\mathrm{5}\:{N} \\…