Search & Filtering
An inclined plane as shown in figure 1 is used to raise an object of mass 30 kg. If the plane is
inclined 5° above the horizontal and the coefficient of friction is 0.20, calculate the ideal
mechanical advantage, actual mechanical advantage, and the efficiency of this machine
A crate of mass 10.0 kg is pulled up a rough incline with an initial speed of 1.5 m/s the pulling
force is 100 N parallel to the incline, which makes an angle of 20° with the horizontal. The
coefficient of kinetic friction 1s 0.4, and the crate is pulled 5.0 m. (a) How much work is done by the
gravitational force on the crate? (b) Determine the increase in internal energy of the crate-incline
system owing to friction. (c) How much work is done by the 100-N force on the crate? (e) What is the
speed of the crate after being pulled 5.0 m
A crate weighing 80 N is pulled along a horizontal surface by a force of 15 N which is applied
20° above the horizontal. If the crate started from rest and the coefficient of friction is 0.15,
determine the kinetic energy and the velocity of the crate after it has moved a distance of 10
m.
A 3.5-kg block rest on a horizontal tabletop. A cord is attached to this block, the cord passing
over a pulley at the edge of the table. At the end of the cord is hung another block weighing
5 N. Determine the tension in the cord and the distance the blocks moved after 2 seconds
1.A cello string vibrates in its fundamental mode with a frequency of 157 1/s. The vibrating segment is 76.9 cm long and has a mass of 0.64 g. Find the tension in the string. Answer in units of N.
2.Find the frequency of the string when it vibrates in six segments. Answer in units of 1/s.
Two students are discussing the motion of the dart-block system at the instant it reaches height H. The
students make the following statements:
Student 1: The speed of the system at height H is zero. Since it is moving in circular motion and
centripetal acceleration is given by , the acceleration must also be zero.
Student 2: The acceleration of the system at height H can’t be zero, or the system would not swing
A block slides from rest from the top of an inclined plane 8 m long which is inclined 35° with the horizontal. If the coefficient of kinetic friction is 0.20, determine how long it will take the block to reach the bottom of the plane.
A 3.5-kg block rest on a horizontal tabletop. A cord is attached to this block, the cord passing
over a pulley at the edge of the table. At the end of the cord is hung another block weighing
5 N. Determine the tension in the cord and the distance the blocks moved after 2 seconds.
How does the elapsed time for a process seem to be longer, an observer moving with the process or observer moving relative to the process? Which observer measures proper time?
A penny is dropped from the roof of a tall building. Find the following measurements; note initial velocity is 0 m/sec.
a) ___________velocity after one second
___________ velocity after two seconds
___________velocity after 3 seconds
b) ___________distance fallen after one second
___________distance fallen after two seconds
___________distance fallen after 3 seconds
2) A football is thrown downward at 18 m/sec.
a) What is the acceleration of the football as it falls?
b) What is the distance it falls after 0.3 seconds?
