6-4 Connected Object

1
6-4 Connected Object

• The several objects tied together motion

• Separate these objects draw free body diagram
• Isolate the object
• Draw the all external forces
• Set up coordinate system
• Resolve the force on x, y axes
• apply Newtons second law

2

• m13.1kg, m24.4kg, find the acceleration?

3

• Two blocks are connected by a string, as shown
  in Figure. The smooth inclined surface makes an
  angle of 350 with the horizontal, and the block
  on the incline has a mass of 5.7kg. The mass of
  the hanging block is m3.2kg, Find acceleration.

4

• M2kg, µk0.3, M4kg, find accelerate and
  tension in rope.

5
6-5 Circular Motion

• changing

6

• Object using the acceleration toward center of
  circle with magnitude

centripetal acceleration
This force causes circular motion and this
centripetal acceleration is called the
centripetal force.
7

• Ex.
• Tension produces centripetal force

Friction is centripetal force
8
ProblemA ball is bonded at v3 m/s what is the
tension in rope? r1.2m (or r3m) m2kg

• Rounding a corner
• A 1200 kg car rounds a corner of radius r-45
  m. if the coefficient of static friction between
  the tires and the road is µs0.82, what is the
  great speed the car can have in the corner
  without skidding.

9

• Banked road
• If a roadway is banked at the proper angle, a
  car can round a corner without any assistance
  from friction between the tires and the road.
  Find the appropriate banking angle for a 900-kg
  car travelling at 20.5 m/s in a turn of radius
  85.0m.