Question

3. The 100 lb block is sliding down the 10° slope with an initial velocity of 8 ft/s when it is acted on by a F = 20.4 lb force. If the coefficient of kinetic friction between the block and the slope is MK = 0.3, determine how much time it takes for the block to reach a velocity of 10 ft/s up the slope. (4.51s) F = 20-t lb 100 lb V. = 8 ft/s A V;= 10 ft/s Mr = 0.3 10°

Answer 1

Subject 4 of using and law motton Vi + at Vf-vi ex = t a -put value of a In this og t = VF - Vi Mk g coso -g sino E + (9= 32ft|s2) 10 -8 20 +(0:3x 32 xcoski0)) -(32x'sinloº) 100 2 0.2 + 9.45 5.56 0:49 sec, 2 4.09 so, Time to reach vi to Vf is 0.49 seca csscanned with CamScanner

F2 20.4 lb Sk 10ftis Наця Ви mgoose ma 11 Giren mass of m = 100 lb + - i ve force 2 NE sox blocks initial veldig ; = 3! final relocity 10ft acting ca a bock, F. 20.11b Coefficient 4 frictim, He = 0:3 angle of inclination, force of kinetic fiction, fx = UKN from ging diagram, macose fk = HK mg cose Since body as the final velocity more than initial velo Velocity Force_acting_onf upside > Force Aeting moting moving and law of motion - Z fnet = ma, F + fk – mgsing FE_Hkmg cose - mg sing ma Hk g cose - gsing accelerating son down and thus, using t using Mewton's of ma. = 317 + CSScanned with CamScanner

F2 20.4 lb Sk 10ftis Наця Ви mgoose ma 11 Giren mass of m = 100 lb + - i ve force 2 NE sox blocks initial veldig ; = 3! final relocity 10ft acting ca a bock, F. 20.11b Coefficient 4 frictim, He = 0:3 angle of inclination, force of kinetic fiction, fx = UKN from ging diagram, macose fk = HK mg cose Since body as the final velocity more than initial velo Velocity Force_acting_onf upside > Force Aeting moting moving and law of motion - Z fnet = ma, F + fk – mgsing FE_Hkmg cose - mg sing ma Hk g cose - gsing accelerating son down and thus, using t using Mewton's of ma. = 317 + CSScanned with CamScanner