P5: MOMENTS, LEVERS AND GEARS

Question 1

What is a pivot?

Answer 1

the point at which an object turns when acted upon by a force

Question 2

What is a moment?

Answer 2

the turning effect of a force

Question 3

What is the equation that links moments, force and distance?

Answer 3

moment (Nm) = force (N) x distance (m) (M = Fd)

Question 4

What is required for a system to reach equilibrium?

Answer 4

all clockwise moments must = anti-clockwise moments

Question 5

How do levers make it easier to achieve the same turning moment?

Answer 5

-levers increase the distance from the pivot at which the force is applied
-since M = Fd, this means less force is required to achieve the same moment

Question 6

Gears

Answer 6

-their teeth interlock so that turning one causes another to turn in the opposite direction
-used to transmit the rotational effect of a force from 1 place to another
-a force transmitted to a larger gear will side a bigger moment as the distance to the pivot is greater
-the larger gear will turn slower than the smaller gear