µ = .575

50kg

20 m

Spring constant = 3kN

Compressed 16 cm

d?

EA - Efriction = EB

PEspr + PEgrav - W = 01/2kx2 + mgh - Ff d = 0

1/2(3000)(.16)2 + 50(9.8)(20) - .575(50)(9.8)d = 0

38.4 + 9800 - 282d = 0

d = 34.9 m

3.0 m

v?

40

3.0 m

v?

40

EA = EB

PEgrav = KE

mgh = 1/2mv2

h

cos40 =X

3

x = 2.3

x

x + h = 3

2.3 + h = 3

h = .7 m

9.8(.7) = ½ v2

v = 3.70 m/s