Look up pulleys problem through Khan academy and a video should pop up with a problem similar and you should be able to walk through it .
Answer:
<em>2.78m/s²</em>
Explanation:
Complete question:
<em>A box is placed on a 30° frictionless incline. What is the acceleration of the box as it slides down the incline when the co-efficient of friction is 0.25?</em>
According to Newton's second law of motion:

Where:
is the coefficient of friction
g is the acceleration due to gravity
Fm is the moving force acting on the body
Ff is the frictional force
m is the mass of the box
a is the acceleration'
Given

Required
acceleration of the box
Substitute the given parameters into the resulting expression above:
Recall that:

9.8sin30 - 0.25(9.8)cos30 = ax
9.8(0.5) - 0.25(9.8)(0.866) = ax
4.9 - 2.1217 = ax
ax = 2.78m/s²
<em>Hence the acceleration of the box as it slides down the incline is 2.78m/s²</em>
A stable air mass is most likely to have POOR SURFACE VISIBILITY.
Stable air mass refers to those air mass that have marked stability in their lower layers. The characteristics of stable air mass include the following: cloud cover, smooth air, uninterrupted precipitation and low visibility.<span />
Answer:
B. 4a
Explanation:
Force between the charges is inversely proportional to the square of the distance
=> Force will be 4 times and acceleration will be 4a
=> Answer b).
Almost all rocks made of minerals, but different rocks contain different mixtures of minerals. Granite<span>, for example, consists of quartz, </span>feldspar<span>, and mica.
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