Gravitational Field Strength

Gravitational field strength is measured in:

• N
• J/kg
• m/s
• N/kg

How do we measure the distance between two objects in the Newton's law of universal gravity?

• Measure from the closest two points between the two objects

• Measure from the furthest two points between the two objects

• Measure from the center of masses between the two objects

• Do not measure at all

Two isolated masses m₁ and m₂ are separated by a distance r. Which expression gives the gravitational field strength caused by m₁ at m₂?

• 
  

  $\frac{Gm_1m_2}{r}$

• $\frac{Gm_1m_2}{r^2}$

• $\frac{Gm_1}{r^2}$

• $\frac{Gm_2}{r^2}$

In this equation...

• G is the gravitational field strength
• r is the distance between the 2 masses
• F is the repulsive gravitational force
• m is the momentum of the mass

Tags

NGSS.HS-PS2-4

The closer together the gravitational field lines.....

• the weaker the gravitational field strength
• the stronger the gravitational field strength
• the more repulsive the gravitational field strength

Tags

NGSS.HS-PS2-4

If an object is placed exactly halfway between Earth and the Moon, it would fall toward the

• Earth.
• Moon.
• neither of these

What is the gravitational field strength at a point one Earth radius above the surface?

• g/2

• g

• g/4

• g/9

Why does an astronaut weigh less on Phobos than on Mars?

• The force of gravity is less on Phobos’s surface than on Mars’s surface.

• The astronaut has less mass on Phobos.

• The astronaut is continually in free fall because Phobos orbits around Mars.

• The astronaut is farther from Mars’s center when he or she is on Phobos.

Saturn has a surface field strength of 10.4 N kg⁻¹ and a radius of 6.03 × 10⁴ km. What is the mass of Saturn?

• 4.7 × 10¹⁸ kg

• 5.7 × 10²⁰ kg

• 4.7 × 10²⁴ kg

• 5.7 × 10²⁶ kg

Tags

NGSS.HS-PS2-4

A mass m is released just above the surface of a planet with mass M and radius R . Which expression gives its initial gravitational acceleration?

• $\frac{Gm}{r^2}$

• $\frac{GmM}{r^{ }}$
  

• $\frac{GmM}{r^2}$
  

• $\frac{GM}{r^2}$