Answer:
460.52 s
Explanation:
Since the instantaneous rate of change of the voltage is proportional to the voltage in the condenser, we have that
dV/dt ∝ V
dV/dt = kV
separating the variables, we have
dV/V = kdt
integrating both sides, we have
∫dV/V = ∫kdt
㏑(V/V₀) = kt
V/V₀ = 
Since the instantaneous rate of change of the voltage is -0.01 of the voltage dV/dt = -0.01V
Since dV/dt = kV
-0.01V = kV
k = -0.01
So, V/V₀ = 
V = V₀
Given that the voltage decreases by 90 %, we have that the remaining voltage (100 % - 90%)V₀ = 10%V₀ = 0.1V₀
So, V = 0.1V₀
Thus
V = V₀
0.1V₀ = V₀
0.1V₀/V₀ =
0.1 =
to find the time, t it takes the voltage to decrease by 90%, we taking natural logarithm of both sides, we have
㏑(0.01) = -0.01t
So, t = ㏑(0.01)/-0.01
t = -4.6052/-0.01
t = 460.52 s
Answer:
B
Explanation:
The control is something that is meant to not be changed, the control is a comparison of the experimental.
Correction
A student measures the mass <em><u>8cm3</u></em> block of brown sugar to be 12.9g. what is the density of the brown sugar
Answer:
Explanation:
Density is defined as mass per unit volume of an object expressed as 
where 
is the density, m is the mass of sugar and v is the volume of the sugar. Considering that the volume is given as 8cm3 for sugar then we substitute this for v and mass of 12.9 g we substitute for g then the density will be
The heat energy released from a piece of wire or any other section of a circuit is:
Energy = (voltage between its ends) x (current through it) x (time it's been going)
Answer:
<em>Thus, the object is accelerating to the left</em>
Explanation:
<u>The Net Force</u>
The net force is the result of adding all the forces as vectors acting on a body.
Each vector can be expressed in its rectangular components Fx and Fy, and the sum is the sum of the rectangular components separately.
Second Newton's law gives the relation between the net force and the acceleration of the body:
We can see the acceleration is a vector with the same direction as the net force.
The diagram shows two vertical forces and two horizontal forces.
The vertical forces are acting in opposite directions and with the same magnitude, thus they cancel out, leaving zero net force in the y-axis.
The horizontal forces are opposite and with different magnitudes. Since the force acting to the left (F3) has a greater magnitude than the force acting to the right (F4), there is a net force directed to the left with a magnitude of 60 N - 20 N = 40 N
Thus, the object is accelerating to the left
