Answer:
A: The acceleration is 7.7 m/s up the inclined plane.
B: It will take the block 0.36 seconds to move 0.5 meters up along the inclined plane
Explanation:
Let us work with variables and set

As shown in the attached free body diagram, we choose our coordinates such that the x-axis is parallel to the inclined plane and the y-axis is perpendicular. We do this because it greatly simplifies our calculations.
Part A:
From the free body diagram we see that the total force along the x-axis is:

Now the force of friction is
where
is the normal force and from the diagram it is 
Thus
Therefore,

Substituting the value for
we get:

Now acceleration is simply

The negative sign indicates that the acceleration is directed up the incline.
Part B:

Which can be rearranged to solve for t:

Substitute the value of
and
and we get:
which is our answer.
Notice that in using the formula to calculate time we used the positive value of
, because for this formula absolute value is needed.
<span>120 revolutions per min is (20RPM)
120revolutions is 240 Pi radians (because 1 revolution is 2Pi rad)
angular velocity
w= 240Pixf, f is the frequency and f= 1/T, T =1mn=60s=period, so f=1/60=0.01Hz
so w = 240*Pi*0.01=12.56 rad /s
linear velocity can be found with
V =Rx w,
V=12.56 R the value depends on what value is the radius of both wheels
</span>
Energy = power × time
1800 = 300 × time
time = 1800 ÷ 300 = 6 s
Hope it helped!
<span>System B: The amorphous silicon solar modules have an efficiency of 6%. The dimensions of the solar modules amount to 0.5m by 1.0m. The output of each module is 30 Wp. The modules cost 20€ each. The advanage of the amorphous silicon solar modules is that they perform better on cloudy days in which there is no direct sunlight. Installed in the Netherlands, this system gives, on a yearly basis, 10% more output per installed Wp than the multicrystalline silicon modules. </span>
<span>System A: The efficiency of the multicrystalline silicon module amounts to 15%. The dimensions of the solar module are 0.5m by 1.0m. Each module has 75 Wp output. The modules cost 60€ each.
</span>