Answer:
The magnitude of the frictional force is
Explanation:
From the question we are told that
The force exerted on the box is
Generally for the box to remain at rest then it means that the frictional force is greater than or equal to the force applied to move it i.e
=>
Answer:
(5/3,-5/6) or (1.67, -0.83)
Explanation:
the center if there are 4 bricks is the point 0,0 or intersection of the two arrow.
if we remove one on the top left, with the center of the mass in (-5,2.5), the the new coordinates of the center of mass can be found like this
x = A1 x1 - A2 x2 / (A1 - A2)
x = new coordinate of the system
A1 is the Area of 4 bricks = 20 x 10 = 200 cm²
A2 is the Area of 1 brick we remove, the top left = 10 x 5 = 50 cm²
x1 = the x coordinate of the center of mass when there are 4 bricks, x = 0
x2 = the x coordinate of the center of mass of the remove brick, x = -5
x = (200 . 0) - (50 . (-5))/(200 - 50)
x = - (-250) / 150
x = 250/150 = 5/3 = 1.67 cm
we can find the value y of the new coordinate, the same way we find x
y = A1 y1 - A2 y2 / (A1 - A2)
y = (200 . 0) - (50 . 2.5) / (200-50)
y = - 125/150
y = -5/6 = -0.83 cm
