Forces, Accelerations and Newton's Law of Motion

Question 1

describe Newton’s first law

Answer 1

if the resultant force acting on an object is zero and:

• the object is stationary, the object remains stationary
• the object is moving, the object continues to move at the same speed and in the same direction - same velocity

Question 2

state what is meant by inertia

Answer 2

a property of matter - the resistance of an object to change its motion

Question 3

describe how to find out which of two objects has the most inertia

Answer 3

• apply an equal force to both of them when they are at rest

- the one that has the greatest acceleration has the lowest inertia: easier to get it to change motion

Question 4

describe Newton’s second law

Answer 4

the acceleration of an object is proportional to the resultant force acting on the object, and is inversely proportional to the mass of the object

Question 5

describe inertial mass

Answer 5

ratio of force divided by acceleration

Question 6

describe Newton’s third law

Answer 6

whenever two objects interact, the forces they exert on each other are equal in size and opposite in direction