Answer:
153.2 J
Explanation:
Let's first list our given parameters;
mass (m) of the block = 10 kg
which slides down ( i.e displacement) = 2 m
kinetic coefficient of friction (μk) = 0.2
In the diagram shown below; if we take an integral look at the component of force in the direction of the displacement; we have
Fcos 40°
100 (cos 40°)
76.60 N
Workdone by the friction force can now be determined as:
W = 
× displacement
W = 76.60 × 2
W = 153.2 J
∴ the work done by the friction force = 153.2 J
Answer: 0.93 mA
Explanation:
In order to calculate the current passing through the water layer, as we have the potential difference between the ends of the string as a given, assuming that we can apply Ohm’s law, we need to calculate the resistance of the water layer.
We can express the resistance as follows:
R = ρ.L/A
In order to calculate the area A, we can assume that the string is a cylinder with a circular cross-section, so the Area of the water layer can be written as follows:
A= π(r22 – r12) = π( (0.0025)2-(0.002)2 ) m2 = 7.07 . 10-6 m2
Replacing by the values, we get R as follows:
R = 1.4 1010 Ω
Applying Ohm’s Law, and solving for the current I:
I = V/R = 130 106 V / 1.4 1010 Ω = 0.93 mA
The magnitude of applied stress in the direction of 101 is 12.25 MPA and in the direction of 011, it is not defined.
<u>Explanation</u>:
<u>Given</u>:
tensile stress is applied parallel to the [100] direction
Shear stress is 0.5 MPA.
<u>To calculate</u>:
The magnitude of applied stress in the direction of [101] and [011].
<u>Formula</u>:
zcr=σ cosФ cosλ
<u>Solution</u>:
For in the direction of 101
cosλ = (1)(1)+(0)(0)+(0)(1)/√(1)(2)
cos λ = 1/√2
The magnitude of stress in the direction of 101 is 12.25 MPA
In the direction of 011
We have an angle between 100 and 011
cosλ = (1)(0)+(0)(-1)+(0)(1)/√(1)(2)
cosλ = 0
Therefore the magnitude of stress to cause a slip in the direction of 011 is not defined.
Answer:
7.65 mm
Explanation:
Stress, 
where F is the force and A is the area
Also, 
Where E is Young’s modulus, L is the length and 
is the elongation
Therefore,
Making A the subject of the formula then
Since 
then
