Forces are responsible for interactions between objects - gravity being one of the most important. An object with mass in a gravitational field experiences a force known as weight.
What are contact forces?
Forces between similar objects
Forces between touching objects
Forces between objects that do not touch
What is a non-contact force?
Forces between objects that are different from each other
What is the unit of force?
What is the gravitational field strength of Earth?
How is weight calculated?
Weight = mass × gravitational field strength
Weight = gravitational field strength ÷ mass
Weight = mass ÷ gravitational field strength
What is the weight of a 40 kg child on Earth (g = 10 N/kg)?
How is the object shown in a free body diagram?
As a drawing of the object
As a written description of the object
As a box or a dot
What way does an arrow point in a free body diagram?
Towards the object
Away from the object
In the direction of movement
A 40 N force and a 30 N force act on an object in the same direction. Which statement is correct?
The resultant force is: 40 + 30 = 70 N
The resultant force is: 40 - 30 = 10 N
The resultant force is: (40 + 30) / 2 = 35 N
Two 30 N forces act on an object in opposite directions. Which statement is correct?
The resultant force is: 30 + 30 = 60 N
The resultant force is: 30 - 30 = 0 N
The resultant force is: 2 × 30 = 60 N