Questions from Modern Physics

Q: One end of a uniform meter stick is placed against a vertical

One end of a uniform meter stick is placed against a vertical wall (Fig. P11.66). The other end is held by a lightweight cord that makes an angle u with the stick. The coefficient of static friction b...

Q: Two friends are carrying a 200-kg crate up a flight

Two friends are carrying a 200-kg crate up a flight of stairs. The crate is 1.25 m long and 0.500 m high, and its center of gravity is at its center. The stairs make a 45.0° angle with resp...

Q: In the human arm, the forearm and hand pivot about the

In the human arm, the forearm and hand pivot about the elbow joint. Consider a simplified model in which the biceps muscle is attached to the forearm 3.80 cm from the elbow joint. Assume that the pers...

Q: You are trying to raise a bicycle wheel of mass m and

You are trying to raise a bicycle wheel of mass m and radius R up over a curb of height h. To do this, you apply a horizontal force

Q: A gate 4.00 m wide and 2.00 m

A gate 4.00 m wide and 2.00 m high weighs 700 N. Its center of gravity is at its center, and it is hinged at A and B. To relieve the strain on the top hinge, a wire CD is connected as shown in Fig. P1...

Q: If you put a uniform block at the edge of a table

If you put a uniform block at the edge of a table, the center of the block must be over the table for the block not to fall off. (a) If you stack two identical blocks at the table edge, the center of...

Q: Two uniform, 75.0-g marbles 2.00

Two uniform, 75.0-g marbles 2.00 cm in diameter are stacked as shown in Fig. P11.75 in a container that is 3.00 cm wide. (a) Find the force that the container exerts on the marbles at the points of co...

Q: Two identical, uniform beams weighing 260 N each are connected at

Two identical, uniform beams weighing 260 N each are connected at one end by a frictionless hinge. A light horizontal crossbar attached at the midpoints of the beams maintains an angle of 53.0Â&...

Q: An engineer is designing a conveyor system for loading hay bales into

An engineer is designing a conveyor system for loading hay bales into a wagon (Fig. P11.77). Each bale is 0.25 m wide, 0.50 m high, and 0.80 m long (the dimension perpendicular to the plane of the fig...

Q: A weight W is supported by attaching it to a vertical uniform

A weight W is supported by attaching it to a vertical uniform metal pole by a thin cord passing over a pulley having negligible mass and friction. The cord is attached to the pole 40.0 cm below the to...