Mechanics Year One

Question 1

What do we assume when there is a smooth surface

Answer 1

Assume there is no friction between the surface and any object on it

Question 2

What do we assume when there is a rough surface

Answer 2

Objects in contact with the surface experience a frictional force if they are moving or are acted on by a force

Question 3

What is air resistance

Answer 3

Resistance experienced as an object moved through the air

Question 4

What do we assume when there is air resistance

Answer 4

Usually modelled as being negligible

Question 5

What is gravity and

Answer 5

Force of attraction between all objects. Acceleration due to gravity is denoted by g, where the value of g=9.8

Question 6

What do we assume about gravity

Answer 6

All objects with mass are attracted towards the earth

Earths gravity is uniform and acts vertically downwards

G is constant and is taken as 9.8 unless otherwise stated in the question

Question 7

What is the opposite force to weight (when a body is on a flat surface)

Answer 7

Normal reaction R

Question 8

What is the opposite of direction of motion

Answer 8

Frictional force

Question 9

What is the opposite to weight when a body is in water

Answer 9

Buoyancy

Question 10

What is opposite to weight when a body is floating

Answer 10

Air resistance

Question 11

What is a vector quantity

Answer 11

A quantity that has both magnitude and direction

Question 12

What is a scalar quantity

Answer 12

Has magnitude only