Its true the ionic compounds have a higher melting point
Answer: -1038.8 kJ
Explanation:
From the question, we can see that PV^n = constant. And as such, we can deduce that it is a polytropic process. Thus, we can use the polytropic work equation to calculate the needed work input.
from the question we were given
Mass of nitrogen, m = 7kg
initial temperature, T1 = 250k
Final temperature, T2 = 450k
Polytropic index, n = 1.4
Specific gas constant, R = 0.2968kJ/kgK
W = [p2 * v2 - p1 * v1] / 1 - n
W = [m * R * T2 - T1] / 1 - n
W = 7*0.2968*(450 - 250)] / 1 - 1.4
W = [7*0.2968*200] / -0.4
W = 415.52 / -0.4
W = -1038.8 kJ
Answer:
D) True. This is what creates the body weight
Explanation:
Let's write Newton's second law for this case. For inclined planes the reference system takes one axis parallel to the plane (x axis) and the other perpendicular to the plane (y axis)
X axis
Wx -fr = ma
Y Axis
N - Wy = 0
With trigonometry we can find the components of weight
sin θ = Wₓ / W
cos θ =
/ W
Wₓ = W sin θ
= W cos θ
W sin θ - fr = ma
From this expression as it indicates that the body is descending the force greater is the gravity that create the weight of the body
Let's examine the answers
A False This force does not apply because it is not a spring
B) False. It is balanced at all times with the component (Wy) of the weight
C) False. For there to be a rope, if it exists you should be less than the weight component for the block to lower
D) True. This is what creates the body weight
E) False. The cutting force occurs for force applied at a single point and gravity is applied at all points