Question

At a certain location, a gravitational force with
a magnitude of 350 newtons acts on a 70.-kilogram
astronaut. What is the magnitude of the gravitational
field strength at this location?
(1) 0.20 kg/N (3) 9.8 m/s2
(2) 5.0 N/kg (4) 25 000 N•kg

Answer 1

The unit of gravitational field strength is Nkg^-1 ie N/kg because the formula for Gravitational field strength is g=F/m where F is the gravitational force and m is the mass, and so by process of elimination, the magnitude of the gravitational field strength at this location is:
5.0 N/kg

Answer 2

The correct answer is: Option (2) 5.0 N/kg

Explanation:

To find the magnitude of the gravitational field strength, you need the formula of weight, which is:

weight = mass * gravitational-field-strength

Where weight is in Newtons, mass is in kilograms and gravitational-field-strength is (Newtons per kilogram).

In this particular scenario, the gravitational force is equal to the weight; please do not confuse weight with a mass. Mass is 70 kg.

Plug in the values:

350 = 70 * gravitational-field-strength

gravitational-field-strength = 350/70

gravitational-field-strength = 5.0 N/kg (Option 2)