Answer:
Yes, this is <em><u>true</u></em>. Hope this helps :)
The law applied here is Newton's first law, also known as, law of inertia.
This law states that: A body will retain its state of rest or motion unless acted upon by an external force.
If you are moving and the bus suddenly stops, your body will lurch forward trying to retain its state of motion until it comes to rest and changes its state by the external force acted on it.
If you are at rest and the bus suddenly moves, your body will lurch backwards trying to retain its state of rest and opposing the force of motion until it is forced to change its state by this force.
Answer: 4.9 x 10-3 N
Explanation:
A = 500cm^2 = 5 x 10^-2 m^2
V = 5 m/s
R = 10^-3 g/cm^2.sec = 10^-2kg/m^2 . sec
Prain water = R / V = 10^-2 / 5 = 2 x 10-3 kg/m^3
For the stationary bowl,
dm/dt =pAv= RA
F= dp/dt = (dm/dt) v = RAv = 2.5 x 10^-3 N
Bowl moving upwards to speed u = 2 m/s
dm/dt = pA ( v + u) / v
F = dp/dt = (dm/dt)(v+u) = RA (v+u)^2 / v = 4.9 x 10^-3 N
The maximum allowable torque must correspond to the allowable shear stress for maximization. To solve this, we use the torsion formula:
Max. Allowable Shear Stress = Maximum Torque ÷ Cross-Sectional Area
8 x 10^6 Pa = Maximum Torque ÷ pi*(d/2)²
Maximum Torque = 8 x 10^6 Pa * pi*(0.06/2)² m²
Maximum Torque = 22,619.47 J or
Maximum Torque = 22.62 kJ
As for the second question, I have no reference figure so I am unable to answer it. I hope I was still able to help you, though.
