When you start sliding the couch, you have to overcome the static friction of the carpeted floor, which is usually very big, especially due to the texture of the carpet. However, as long as you get it moving, you only have to apply the force to overcome the kinetic friction, which is smaller than the static friction.
Answer:
Ohm's Law
Explanation:
The relationship: 
where V represents the voltage across a resistor of resistance "R" through which a current (I) flows,
is known as Ohm's Law in honor of Georg Ohm, who discover this proportionality.
Answer:
The answer is B. composition
Explanation:
- The speed of a seismic wave is governed by three interrelated factors, viz. the composition of the rock, pressure, and temperature.
- Seismic waves travel at different speeds in different mediums.
- This property of the seismic waves tends it to change the speed where the concentration of minerals in the rocks varies.
- Other than that, the increasing temperature beneath the Earth's surface decreases the speed of the seismic waves, and the speed increases with increasing pressure as the waves go penetrating deep down into the Earth's interiors.
Answer:
The function is x = e^(-t/2) * (0.792*sin12t + 5cos12t)
Explanation:
we have to:
m = mass = 4 kg
k = spring constant = 577 N/m
c = damping constant = 4 N*s/m
The differential equation of motion is equal to:
m(d^2x/dt^2) + c(dx/dt) + k*x = 0
Replacing values:
4(d^2x/dt^2) + 4(dx/dt) + 577*x = 0
Thus, we have:
4*x^2 + 4*x + 577 = 0
we will use the quadratic equation to solve the expression:
x = (-4 ± (4^2 - (4*4*577))^1/2)/(2*4) = (-4 ± (-9216))/8 = (1/2) ± 12i
The solution is equal to:
x = e^(1/2) * (c1*sin12t + c2*cos12t)
x´ = (-1/2)*e^(1/2) * (c1*sin12t + c2*cos12t) + e^(-t/2) * (12*c1*cos12t - 12*c2*sin12t)
We have the follow:
x(0) = 5
e^0(0*c1 + c2) = 5
c2 = 5
x´(0) = 7
(-1/2)*e^0 * (0*c1 + c2) + e^0 * (12*c1 - 0*c2) = 7
(-1/2)*(5) + 12*c1 = 7
Clearing c1:
c1 = 0.792
The function is equal to:
x = e^(-t/2) * (0.792*sin12t + 5cos12t)
Answer:
There is no mechanical advantage
Explanation:
The mechanical advantage is possible only when the force needed to lift a load is lesser than the weight of the load.
For example, is we have a mechanical advantage of 2, the force needed to lift will be 1/2 of the weight of the load, and if we have a mechanical advantage of 4, the force needed will be 1/4 of the weight of the load.
In the attached image there are clear examples of mechanical advantage with pulleys.
