Answer:
dr/dt = -2 cm/s.
Explanation:
The volume of a cone is given by:
(1)
- r is the radius
- h is the height
Let's take the derivative with respect to time in each side of (1).
(2)
We know that:
- dh/dt = 10 cm / s (rate increasing of height)
- dV/dt = 0 (constant volume means no variation with respect of time)
- r = 4 cm
- h = 10 cm
We can calculate how fast is the radius changing using the above information.
Therefore dr/dt will be:
The minus signs means that r is decreasing.
I hope it helps you!
Answer:
240000 Joules
Explanation:
Applying,
The work that must be done by the frictional force of the brake to stop the car must be equal to the kinetic energy of the car.
W = mv²/2.................. Equation 1
Where W = work done by the frictional force of the brake, m = mass of the car, v = velocity of the car.
From the question,
Given: m = 1200 kg, v = 20 m/s
Substitute these values into equation 1
W = (1200×20²)/2
W = 240000 Joules
Answer:
The answer to your question is a = -1.85 m/s² the acceleration is negative because it is coming to stop.
Explanation:
Data
vo = 25 m/s
t = 13.5 s
a= ?
vf = 0 m/s
Formula
vf = vo + at
solve for a
a = (vf - vo)/t
Substitution
a = (0 - 25) / 13.5
Simplification
a = -25/13.5
Result
a = -1.85 m/s²
Answer:
it depends on the relative masses of the objects.
Explanation:
