Mechanics

Question 1

Difference between buoyancy and upthrust

Answer 1

Buoyancy is the ability of an object to float in a fluid whereas upthrust is a force exerted on a submerged object by a fluid

This fluid can be a liquid or gas

Question 2

inclined plane

Answer 2

slope

Question 3

An apple with a weight of 1.5 N is at rest on an inclined plane at 29° to the horizontal. Find the component
of its weight that acts along the slope.

Answer 3

• Draw a diagram - the angle between the slope and horizontal component = 29°
• Using the horizontal and vertical components to form a triangle, you can find that the angle between the length we are looking for (W1) = 90 - 29 = 61°, and therefore the angle between W1 and its perpendicular bisector is also 29°
• Use trigonometry to find the magnitude of W1 ->
  sin(29) = W1 / 1.5
  W1 = 0.7272… ~ 0.73N