Dynamics

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Two blocks, of masses *m*_{A} = 0.35 kg and *m*_{B} = 1.15 kg, are on a frictionles
horizontal surface, the blocks are connected by a rope with negligible mass. A horizontal force of constant
magnitude equal to 15 N is applied by pulling the two blocks. Find the magnitude acceleration acquired by the
system and the tension in the rope connecting the blocks.

A locomotive, mass 130 t, drags a railroad car, mass 120 t. The maximum force that the locomotive coupler can withstand is 2,900 kN. Find the maximum driving force that the locomotive can exert in order not to break the coupler. Disregard resistance forces.

An Atwood machine has masses, of *m*_{A} = 6.25 kg and *m*_{B} = 6.75 kg, connected
by a weightless cord, through a pulley frictionless. Find:

a) The acceleration of the system;

b) The tension in the rope connecting the masses;

c) The tension in the rope that holds the system to the ceiling.

Assume the free-fall acceleration*g* = 10 m/s^{2}.

a) The acceleration of the system;

b) The tension in the rope connecting the masses;

c) The tension in the rope that holds the system to the ceiling.

Assume the free-fall acceleration

In the system of the figure, the body *A* slides on a horizontal surface without friction, dragged by body
*B* that moves downward. Bodies *A* and *B* are attached by a rope of negligible mass parallel to the
surface and passing through a frictionless pulley of negligible mass. The masses of *A* and *B* are respectively
32 kg and 8 kg. Find the acceleration of the system and the tension on the cord. Assume
*g* = 10 m/s^{2}.

In the system of the figure, the body *B* slides on a horizontal surface without friction, it is connected through
by ropes and pulleys, lightweight and frictionless, with two bodies *A* and *C* that move vertically. The
masses of *A*, *B*, and *C* are, respectively, 5 kg, 2 kg and 3 kg. Find the acceleration of the system
and the tension in the cord. Assume *g* = 10 m/s^{2}.

In an Atwood machine, the two bodies at rest on a horizontal surface, are connected by a cord, of negligible mass,
that passes over a frictionless pulley of negligible mass. The masses weight *m*_{A} = 24 kg and
*m*_{B} = 40 kg and the free-fall acceleration *g* = 10 m/s^{2}.
Find body accelerations when:

a)*F* = 400 N;

b)*F* = 720 N;

c)*F* = 1200 N.

a)

b)

c)

On a windless day, a car travels at a constant speed of 72 km/h, the constant associated with the car shape (*c*)
is equal to 0.6 *SI* units (*International System of Units*), and the perpendicular area to the direction
of motion is 3 m^{2}. Find the magnitude of the air resistance force.

A high-speed train travels a 2500 m radius curve at a speed of 270 km/h, determine:

a) The centrifugal force felt by a passenger of a mass of 70 kg in a wagon;

b) What should be the speed of a car, traveling a 10 m radius curve, so that the passenger of the train felt the same centrifugal force being in the car. Answer in km/h.

a) The centrifugal force felt by a passenger of a mass of 70 kg in a wagon;

b) What should be the speed of a car, traveling a 10 m radius curve, so that the passenger of the train felt the same centrifugal force being in the car. Answer in km/h.

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Fisicaexe - Physics Solved Problems by Elcio Brandani Mondadori is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License .