Questions from Modern Physics

Q: A sphere with radius R = 0.200 m has density

A sphere with radius R = 0.200 m has density r that decreases with distance r from the center of the sphere according to r = 3.00 × 103 kg/m3 –(9.00 × 103 kg/m4)r. (a) Calculate the total mass of the...

Q: The Crab Nebula is a cloud of glowing gas about 10 light

The Crab Nebula is a cloud of glowing gas about 10 light years across, located about 6500 light-years from the earth (Fig. P9.86). It is the remnant of a star that underwent a supernova explosion, se...

Q: A technician is testing a computer-controlled, variable-speed

A technician is testing a computer-controlled, variable-speed motor. She attaches a thin disk to the motor shaft, with the shaft at the center of the disk. The disk starts from rest, and sensors attac...

Q: You are analyzing the motion of a large flywheel that has radius

You are analyzing the motion of a large flywheel that has radius 0.800 m. In one test run, the wheel starts from rest and turns with constant angular acceleration. An accelerometer on the rim of the f...

Q: You are rebuilding a 1965 Chevrolet. To decide whether to replace

You are rebuilding a 1965 Chevrolet. To decide whether to replace the flywheel with a newer, lighter-weight one, you want to determine the moment of inertia of the original, 35.6-cm-diameter flywheel....

Q: At a construction site, a 65.0-kg bucket

At a construction site, a 65.0-kg bucket of concrete hangs from a light (but strong) cable that passes over a light, friction-free pulley and is connected to an 80.0-kg box on a horizontal roof (Fig....

Q: Two blocks with different masses are attached to either end of a

Two blocks with different masses are attached to either end of a light rope that passes over a light, frictionless pulley suspended from the ceiling. The masses are released from rest, and the more ma...

Q: A small block with mass 0.0400 kg is moving in

A small block with mass 0.0400 kg is moving in the xy-plane. The net force on the block is described by the potential- energy function U(x, y)=(5.80 J/m2)x2 –(3.60 J/m3)y3. What are the magnitude and...

Q: A block with mass 0.50 kg is forced against a

A block with mass 0.50 kg is forced against a horizontal spring of negligible mass, compressing the spring a distance of 0.20 m (Fig. P7.39). When released, the block moves on a horizontal tabletop fo...

Q: A 2.00-kg block is pushed against a spring

A 2.00-kg block is pushed against a spring with negligible mass and force constant k = 400 N/m, compressing it 0.220 m. When the block is released, it moves along a frictionless, horizontal surface an...