Acceleration = (final velocity^2 - initial velocity^2) / 2 * distance
Acceleration = (19.1^2 - 9.2^2) / 2 * 32
Acceleration = (364.81 - 84.64) / 64
Acceleration = 280.17 / 64
Acceleration = 4.3777m/s^2
:)
Answer:
Approximately 
, assuming that the acceleration of this ball is constant during the descent.
Explanation:
Assume that the acceleration of this ball, 
, is constant during the entire descent.
Let 
denote the displacement of this ball and let 
denote the duration of the descent. The SUVAT equation 
would apply.
Rearrange this equation to find an expression for the acceleration, , of this ball:
.
Note that 
and 
in this question. Thus:
.
Let 
denote the mass of this ball. By Newton's Second Law of Motion, if the acceleration of this ball is , the net external force on this ball would be 
.
Since 
and 
, the net external force on this ball would be:
.
Answer:
b bc they are a dangerous threat to humans health
Answer:
Wt = 26.84 [N]
Explanation:
In order to solve this problem we must use the definition of work in physics. Which tells us that this is equal to the product of force by distance.
In this case, we must sum the works of the force applied by the box and the friction force that also acts on the box.
The friction force is defined as the product of the normal force by the coefficient of friction.
f = N*μ
where:
N = normal force = m*g [N] (units of Newtons)
m = mass = 72 [kg]
g = gravity acceleration = 9.81 [m/s²]
f = friction force [N]
μ = friction coefficient = 0.21
f = 72*9.81*0.21
f = 148.32 [N]
Now the total work:
Wt = WF - Wf
where:
Wt = total work [J] (units of Joules)
WF = work by the pushing force [J]
Wf = work done by the friction force [J]
Wt = (160*2.3) - (148.32*2.3)
Wt = 26.84 [N]
Note: The friction force exerts a negative work, because this force is acting in opposite direction to the movement, therefore the negative sign.
Answer:
P = 23.32 W
Explanation:
In series
equivalent Resistance
R(eq)=R+R=2R
In parallel equivalent resistance
R(eq) = R*R/(R+R) =R/2
since.
power
P=V² / R
in series
⇒V = √(P*R)
=√(5.83*2R
)
=√(11.66R)
in parallel
P = V² / R(eq)
=(√(11.66R)²) / (R/2)
P=11.66 * R * 2/R
P = 23.32 W
