Answer:
1.4m/s
Explanation:
Average velocity is the total distance covered divided by the total time taken.
Average velocity =
Total time taken = 5s + 6s = 11s
The first distance covered = velocity x time = 1.4 x 5 = 7m
second distance covered = velocity x time = 1.4 x 6 = 8.4m
So;
Average velocity = = 1.4m/s
To solve the problem it is necessary to use Newton's second law and statistical equilibrium equations.
According to Newton's second law we have to
where,
m= mass
g = gravitational acceleration
For the balance to break, there must be a mass M located at the right end.
We will define the mass m as the mass of the body, located in an equidistant center of the corners equal to 4m.
In this way, applying the static equilibrium equations, we have to sum up torques at point B,
Regarding the forces we have,
Re-arrange to find M,
Therefore the maximum additional mass you could place on the right hand end of the plank and have the plank still be at rest is 16.67Kg
Answer:
b. 0.034
Explanation:
The heat transfer coefficient of a material (U-value) is equal to the reciprocal of its R-value, therefore:
where
R is the R-value of the material
For the insulator in this problem,
R = 29
Substituting into the equation, we find the heat transfer coefficient: