It’s going to be both answer A and B but if you can only answer one then it’s going to be B
The SI unit for acceleration is m/s2 ( D)
Answer:
D.None of these
Explanation:
The derivation of acceleration formula:
Let us call the 5kg mass 
and the 4kg mass 
. If the tension in the string is 
then for the mass
(1). 
<em>(the negative sign on the right side indicates that acceleration is downwards)</em>
And for the mass
(2). 
<em> (the acceleration is upwards, hence the positive sign)</em>
Solving for in the 2nd equation we get:
,
and putting this into the 1st equation we get:
Back to the question:
Using the formula for the acceleration we find
which is the acceleration that none of the given choices offer. Also, the acceleration of the two blocks is the same, because if it weren't, the difference in the instantaneous velocities of the objects would cause the string to break. Therefore, these two reasons make us decide that none of the choices are correct.
Answer:
See below
Explanation:
Normal force = m g cos 53 = 8 kg * 9.8 m/s^2 * cos 53 = 47.1823 N
no work is done by this force
Force friction = coeff friction * force normal = .4 * 47.1823 = 7.55 N
work of friction = 7.55 * 2 m = 15.1 j
Force Downplane = mg sin 53 = 62.61 N
work = 62.61 * 2 = 125.22 j
Net Force downplane = force downplane - force friction = 55.06 N
net Work = force * distance = 55.06 N * 2 M = 110.12 j
Blue puprle white gold organs yellow red gray brown green pink black tan light blue
