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!
1.3s
Explanation:
Given parameters:
Height = 1.4m
Gravity on moon = 1.67ms⁻¹
Unknown:
Time for feather to fall = ?
Solution:
To solve this problem, we are going to use one of the motion equation that relates time, gravity and height.
H = ut + 
Sine the body was dropped from rest, initial velocity is zero;
H = height
u = initial velocity
t = time
g = acceleration due to gravity
since u = 0;
H = 
1.4 =
x 1.67 x t²
t = 1.3s
learn more:
Gravity brainly.com/question/10934170
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0.975 is correct, to get the answer you divide the length value by 10.
The sketch of the system is: two strings, 1 and 2, are attached to the ceiling and to a third string, 3.The third string holds the bag of cement.
The free body diagram of the weight with the string 3, drives to the tension T3 = weihgt => T3 = 325 N
The other free body diagram is around the joint of the three strings.
In this case, you can do the horizontal forces equilibrium equation as:
T1* cos(60) - T2*cos(40) = 0
And the vertical forces equilibrium equation:
Ti sin(60) + T2 sin(40) = T3 = 325 N
Then you have two equations with two unknown variables, T1 and T2
0.5 T1 - 0.766 T2 = 0
0.866 T1 + 0.643T2 = 325
When you solve it you get, T1 = 252.8 N and T2 = 165 N
Answer: T1 = 252.8 N, T2 = 165N, and T3 = 325N
Answer:
Vertical velocity decreases.
Explanation:
The motion of the ball is a projectile ball, which consists of two independent motions:
- a horizontal motion, with constant velocity
- a vertical motion, with constant acceleration g=9.8 m/s^2 towards the ground
In the vertical motion, there is a constant acceleration directed downward: this means that the vertical velocity decreases as the ball goes higher. In fact, it decreases following the equation

And it decreases until the ball reaches its maximum height, then it starts increasing again.