a sled is initially given a shove up a frictionless 28.0 degree incline.it reaches a maxinum vertical height 1.35m higher than where it started. what was the initial speed? if the incline has friction of f=20N and the sled has mass m=5kg, determine the vertical height reached by the sled suppose it is given the same initial speed as in 5.14m/s.

Question

aaronq · Answer

Use the conservation of energy for the first part: $\sf KE_f+PE_f=KE_i+PE_i$

For the second part you need to sum up the forces and use newton's second law

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$\sf \sum F_x=-sin(28^o)F_g-f=ma$

$\sf \sum F_x=n-sin(28^o)F_g=0$

Use $\sf v_f^2=v_i^2+2a\Delta x$ find the distance travelled up the ramp

Use trigonometry to find the height reached.