Review Assignment Kinetics
Kinetics, the study of unbalanced forces causing motion, can be analyzed by three methods: inertia force or torque (dynamic equilibrium), work and energy, and impulse and momentum.
Consider the following as you complete your assignment:
· For linear motion the inertia force is
· Equal to ma
· Acting through the center of gravity
· Opposite in direction to the acceleration
· For rotational motion the inertia torque is
· Equal to C
· Opposite in direction to the angular acceleration
· For a plane motion problem such as a rolling cylinder, try to
· Equate or relate linear acceleration to angular acceleration.
· Take moments at the rolling point of contact with the surface.
Chapter 13: Kinetics
· Section: Problems
· 13-1
Determine the acceleration of the 150-lb block in Figure P131 if the coefficient of kinetic friction is 0.4.
a = 9.05 ft/s^2 ?
· 13-3
A 130-kg cart is accelerated horizontally by a 250-N force pulling at an angle of 20° above horizontal. Neglecting rolling resistance, determine the acceleration of the cart.
a = 1.81 m/s^2
· 13-7
At what maximum acceleration rate can a 500-N test-strength cable lift a 40-kg mass?
a = 2.69 m/s^2 ?
· 13-8
What force does a 180-lb man exert on the floor of an elevator that is moving downward and decelerating at 15 ft/s2?
264 lb
· 13-20
The coefficient of kinetic friction for mass B in Figure P1320 is 0.25. Determine the acceleration of mass A if it has a mass of (a) 30 kg and (b) 50 kg.
aA = 0.76 m/s^2 aA = 0
· 13-36
A 1000-kW generator has a 3500-lb rotor that is accelerated from rest to 3600 rpm in 10 seconds. Determine the torque required. Assume the rotor to be a solid cylinder 40 in. in diameter.
T = 5690 lb-ft
· 13-41
A 150-mm-diameter shaft with a mass of 20 kg is rotating at 900 rpm. A pulley mounted on the shaft has a mass moment of inertia of 0.15 kg ? m2. If the shaft and the pulley coast to a stop due to a tangential frictional force of 8lb at the outer radius of the shaft, determine the time required.
58.9 s
Recent Comments