Physics: Fluid Mechanics, Gravity, and Orbital Mechanics Quiz

What is the radius of a sphere with a density of 5000 kg/m3 and a mass of 6.00 kg?

6.59 cm

At which of the indicated points in a fluid container is the pressure greatest?

The pressure is the same at each of the labeled points.

What is the density of a fluid if the gauge pressure at the top of a cubical box is 594 Pa and at the bottom is 1133 Pa?

1100 kg/m3

Which block has the greater buoyant force: a 50-cm3 block of wood floating partially submerged in water or a 50-cm3 block of iron totally submerged in water?

The iron

Compared to fresh water, how does the volume of salt water displaced by a ship floating in both compare?

Less than the volume of fresh water.

If you double the pressure on the surface of a can of water, what happens to the buoyant force on a stone placed in that water?

It will not change.

What is the tension in the cord supporting a 7.8-kg solid sphere made of metal with a density of 2500 kg/m3 when immersed in water?

46 N

What is the speed of fluid flow at a second position in a pipe if the pressure is 200 kPa and the first position has a pressure of 300 kPa and a speed of 20.0 m/s?

23.8 m/s

What is the fluid speed at a location where the diameter of a pipe narrows from 8.0 cm to 4.0 cm if the speed at 8.0 cm is 1.28 m/s?

5.12 m/s

What is the minimum speed needed to escape from the surface of a spherical asteroid with a mass of 3.5 × 10^16 kg and a radius of 8.8 km?

23 m/s

What is the correct ranking of objects from highest to lowest average density: A, B, C, D, E?

EDABC

What is the difference in elevation h if the manometer reading m is 25.0 cm and the water density is 1000 kg/m3 with mercury density of 13,600 kg/m3?

3.15 m

What is true about the gravitational force on a baseball located at the surface of the earth?

The gravitational force on the ball due to the earth is exactly the same as the gravitational force on the earth due to the ball.

At what distance above the earth's surface will the acceleration of gravity be 4.9 m/s2 if the radius of the earth is R?

0.41 R

What is the speed of a rock when it hits earth's surface if it passes the top of a tower three earth radii high with speed v1?

2v1

What is true about the torque that the sun exerts on a planet moving in an elliptical orbit?

It is zero at all times.

How does the orbital speed of the earth change when it is closer to the sun?

Greater than when the earth is farthest away from the sun.

What is true about two planets having equal masses in circular orbit around a star, where Planet A has a smaller orbital radius than Planet B?

Planet A has more kinetic energy, less potential energy, and less mechanical energy than Planet B.

If a certain planet has an escape speed V, what is the escape speed of another planet of the same size with twice the mass?

Square root of 2V

What is the orbital speed of an ice cube in the rings of Saturn if the mass of Saturn is 5.68 × 10^26 kg and the average radius of the rings is 100,000 km?

19.5 km/s