Part IV a) An 8.00 kg mass is at rest on an incline, the angle of the incline is

Question

Part IV a) An 8.00 kg mass is at rest on an incline, the angle of the incline is 32.0°. The incline has a rough surface (Ha-0375 and .-0.250). A force F is applied to the mass in the horizontal direction. toward the direction up the incline. Find the force F where the motion of the object up the incline is Simulate on IP and determine the applied force F. Determine the % error. b) Add 2.00 N to your value for F found in part a). Calculate how fast the object is moving after a displacement of 15.0 m up the incline, and how long it would take for the object to travel this distance. Simulate on IP and determine the % errors in the speed and the time.

Explanation / Answer

When F is applied in the horizontal direction, resolving the force towards incline and normal to it

So force pushing the block up the incline = F cos(32)

Force normal = Fsin(32)

Also force due to the weight of the block = 8*9.81= 78.48 N

Force down the incline due to weight = 78.48 sin(32) =41.59 N

Total normal force = 78.48 cos32 + F sin 32

So for the movement of block = F cos32 >= 41.59+ mus*( 78.48 cos32 + F sin 32)

0.65 F = 66.55 N

F = 102.38 N (ans)

b) Now increasing the force by 2 N

F= 104.38

Then net force upward = 104.38 cos32 - 41.59 - muk*( 78.48 cos32 + 104.38 sin 32) = 16.46 N

Net accleration = 16.46 /8 = 2.06 m/sec^2

V^2 = 2as = 2*2.06*15

V = 7.86 m/sec (ans)

t^2= 2s/a = 30/2.06 =

t = 3.82 sec (ans)

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---