Questions from College Physics

Q: A fish uses a swim bladder to change its density so it

A fish uses a swim bladder to change its density so it is equal to that of water, enabling it to remain suspended under water. If a fish has an average density of 1080 kg/m3 and mass 10.0 g with the b...

Q: A 0.122 kg dart is fired from a gun with

A 0.122 kg dart is fired from a gun with a speed of 132 m/s horizontally into a 5.00 kg wooden block. The block is attached to a spring with a spring constant of 8.56 N/m. The coefficient of kinetic f...

Q: A solid piece of plastic, with a density of 890 kg

A solid piece of plastic, with a density of 890 kg/m3, is placed in oil with a density of 830 kg/m3 and the plastic sinks (1). Then the plastic is placed in water and it floats (2). (a) What percenta...

Q: A car traveling at 29 m/s runs into a bridge

A car traveling at 29 m/s runs into a bridge abutment after the driver falls asleep at the wheel. (a) If the driver is wearing a seat belt and comes to rest within a 1.0 m distance, what is his accel...

Q: For a system of three particles moving along a line, an

For a system of three particles moving along a line, an observer in a laboratory measures the following masses and velocities. What is the velocity of the CM of the system?

Q: Why does a 1 kg sandbag fall with the same acceleration as

Why does a 1 kg sandbag fall with the same acceleration as a 5 kg sandbag? Explain in terms of Newton's second law and his law of gravitation.

Q: A square loop of wire of side 3.0 cm carries

A square loop of wire of side 3.0 cm carries 3.0 A of current. A uniform magnetic field of magnitude 0.67 T makes an angle of 37° with the plane of the loop. (a) What is the magnitude of the torque on...

Q: A plate of uniform thickness is shaped as shown. Where is

A plate of uniform thickness is shaped as shown. Where is the center of gravity? Assume the origin (0, 0) is located at the lower left corner of the plate; the upper left corner is at (0, s); and the...

Q: Nine-banded armadillos (Dasypus novemcinctus) have a typical mass

Nine-banded armadillos (Dasypus novemcinctus) have a typical mass density of 1200 kg/m3 and a mass of 7.0 kg (including their armor). When faced with a body of water to cross, the armadillo has two ch...

Q: A pilot without special training or equipment can tolerate a horizontal acceleration

A pilot without special training or equipment can tolerate a horizontal acceleration of up to about 9g for a short period of time (about a minute) without losing consciousness. (a) How long would it...