Answer:
A. True
Explanation:
When a stone is thrown straight-up, it has an initial velocity which decreases gradually as the stone move to maximum height due to constant acceleration due to gravity acting downward on the stone, at the maximum height the final velocity of the stone is zero. As the stone descends the velocity starts to increase and becomes maximum before it hits the ground.
Height of the motion is given by;
g is acceleration due to gravity which is constant
H is height traveled
u is the speed of throw, which determines the value of height traveled.
Therefore, when the stone is caught at the same height from which it was thrown in the absence of air resistance, the speed of the stone when thrown will be equal to the speed when caught.
Answer:54.70 N
Explanation:
Given
Gauge Pressure of 
i.e. 
Effective area 
initial Pressure
Gauge Pressure 
Force creates a pressure of 
which will be equal to Gauge Pressure
Answer:
The constant angular acceleration of the centrifuge = -252.84 rad/s²
Explanation:
We will be using the equations of motion for this calculation.
Although, the parameters of this equation of motion will be composed of the angular form of the normal parameters.
First of, we write the given parameters.
w₀ = initial angular velocity = 2πf₀
f₀ = 3650 rev/min = (3650/60) rev/s = 60.83 rev/s
w₀ = 2πf₀ = 2π × 60.83 = 382.38 rad/s
θ = 46 revs = 46 × 2π = 289.14 rad
w = final angular velocity = 0 rad/s (since the centrifuge come rest at the end)
α = ?
Just like v² = u² + 2ay
w² = w₀² + 2αθ
0 = 382.38² + [2α × (289.14)]
578.29α = -146,214.4644
α = (-146,214.4644/578.29)
α = - 252.84 rad/s²
Hope this Helps!!!
Answer:
Yes, if the system has friction, the final result is affected by the loss of energy.
Explanation:
The result that you are showing is the conservation of mechanical energy between two points in the upper one, the energy is only potential and the lower one is only kinetic.
In the case of some type of friction, the change in energy between the same points is equal to the work of the friction forces
= ΔEm
= 
-Em₀
As we can see now there is another quantity and for which the final energy is lower and therefore the final speed would be less than what you found in the case without friction.
= + Em₀
Remember that the work of the rubbing force is negative, let's write the work of the rubbing force explicitly, to make it clearer
½ m v² = -fr d + mgh
v = √(-fr d 2/m + 2 gh)
v = √ (2gh - 2fr d/m)
Now it is clear that there is a decrease in the final body speed.
Consequently, if the system has friction, the final result is affected by the loss of energy.
Answer:
True
Explanation:
This is a universal rule for all standard motor vehicles.
