Questions from College Physics

Q: When photons with a wavelength of 120.0 nm are incident

When photons with a wavelength of 120.0 nm are incident on a metal, electrons are ejected that can be stopped with a stopping potential of 6.00 V. (a) What stopping potential is needed when the photo...

Q: A stone used to grind wheat into flour is turned through 12

A stone used to grind wheat into flour is turned through 12 revolutions by a constant force of 20.0 N applied to the rim of a 10.0 cm radius shaft connected to the wheel. How much work is done on the...

Q: An inexperienced catcher catches a 130 km/h fastball of mass

An inexperienced catcher catches a 130 km/h fastball of mass 140 g within 1 ms, whereas an experienced catcher slightly retracts his hand during the catch, extending the stopping time to 10 ms. What a...

Q: If a car (mass 1200 kg) traveling at 28 m

If a car (mass 1200 kg) traveling at 28 m/s is brought to a full stop in 4.0 s after the brakes are applied, find the average frictional force exerted on the car.

Q: A piece of metal is released under water. The volume of

A piece of metal is released under water. The volume of the metal is 50.0 cm3 and its specific gravity is 5.0. What is its initial acceleration?

Q: A stationary 0.1 g fly encounters the windshield of a

A stationary 0.1 g fly encounters the windshield of a 1000 kg automobile traveling at 100 km/h. (a) What is the change in momentum of the car due to the fly? (b) What is the change of momentum of th...

Q: A garden hose of inner radius 1.0 cm carries water

A garden hose of inner radius 1.0 cm carries water at 2.0 m/s. The nozzle at the end has inner radius 0.20 cm. How fast does the water move through the nozzle?

Q: A 0.15 kg baseball is pitched with a speed of

A 0.15 kg baseball is pitched with a speed of 35 m/s (78 mi/h). When the ball hits the catcher's glove, the glove moves back by 5.0 cm (2 in.) as it stops the ball. (a) What was the change in momentu...

Q: If the average volume flow of blood through the aorta is 8

If the average volume flow of blood through the aorta is 8.5 × 10−5 m3/s and the cross-sectional area of the aorta is 3.0 × 10−4 m2, what is the average speed of blood in the aorta?

Q: An object of mass 2.0 kg (the “projectile

An object of mass 2.0 kg (the “projectile”) approaches a stationary object (the “target”) at 8.0 m/s. The projectile is deflected through an angle of 90.0° and its speed after the collision is 6.0 m/s...