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lilianaluciagm
Oct 27, 2008, 02:21 PM
A physics student pulls a block of mass m = 22 kg up an incline at a slow constant velocity for a distance of d = 3 m. The incline makes an angle q = 29° with the horizontal. The coefficient of kinetic friction between the block and the inclined plane is ľk = 0.3.

WORKdone=479.15

b)What is the speed v of the block when it first reaches the horizontal surface?
v=sqrt(2.g.h-u.g.cos (Q))
is that right but what is h?
3*sin 29?

c)What is the spring constant k of the spring?
d)How far up the incline d1 does the block rebound?

Thank you

ebaines
Oct 27, 2008, 02:57 PM
The first part looks good - that's the sum of the work done against friction plus the work against gravity.

Part b - what horizontal surface? Is there a figure? Your equation for v does not look right - how did you get that? Are you trying to figure out the velocity of the block if you let it slide back down hill?

Part C - what spring? Again - you need to include a figure or better description.