Answer:
Rotate a semicircle 180° about its diameter
Step-by-step explanation:
For common figures, the shape of a figure that revolves about a line which is at the base of the figure to give a 3 dimensional shape is the shape of the cross section of the 3 dimensional figure when the angle of revolution is 180° and half the shape of the cross section of the formed 3 dimensional figure, when the angle of revolution is 360°
The cross section of an hemisphere is a semicircle, therefore, the shape of an hemisphere is formed by rotating a semicircle 180° about the diameter (which is the straight line at the "base") of the semicircle
Therefore;
The correct option that gives the revolution that will generate the hemisphere is;
Rotate a semicircle 180° about its diameter.
If Anouk does 150 J of work using a hammer to pull a nail out of a piece of wood, and the hammer does 105 J of work on the nail then the efficiency of the hammer is 70%
<h3>What is efficiency ?</h3>
Efficiency is the ability to avoid wasting materials, energy, efforts, money, and time in doing something or in producing a desired result.
Given that Anouk does 150 J of work using a hammer to pull a nail out of a piece of wood, and the hammer does 105 J of work on the nail.
Efficiency of hammer can be calculated as
efficiency = output obtained / input given
E=105/150
E=7/10
E=0.7
Converting into percentage
If Anouk does 150 J of work using a hammer to pull a nail out of a piece of wood, and the hammer does 105 J of work on the nail then the efficiency of the hammer is 70%
To learn more about efficiency visit : brainly.com/question/477376
It is c because it is I just did if give me Brainly
Hi there!
We have:
-3 - x = -2w + 4v
Solve for x
Start by adding 3 to both sides
-3 - x + 3 = -2w + 4v + 3
-x = -2w + 4v + 3
Remember that we cannot leave the x with a negative sign.
There are two ways to remove the negative sign.
1) We can divide both sides by -1
2) We can multiply both sides by -1
In this, I am going to multiply both sides by -1
-x * -1 = (-2w + 4v + 3)(-1)
x = 2w - 4v - 3
I hope this helps.
Please let me know if you have questions about the answer.
Thanks!
Answer:
ρ_air = 0.15544 kg/m^3
Step-by-step explanation:
Solution:-
- The deflated ball ( no air ) initially weighs:
m1 = 0.615 kg
- The air is pumped into the ball and weight again. The new reading of the ball's weight is:
m2 = 0.624 kg
- The amount of air ( mass of air ) pumped into the ball can be determined from simple arithmetic between inflated and deflated weights of the ball.
m_air = Δm = m2 - m1
m_air = 0.624 - 0.615
m_air = 0.009 kg
- We are to assume that the inflated ball takes a shape of a perfect sphere with radius r = 0.24 m. The volume of the inflated ( air filled ) ball can be determined using the volume of sphere formula:
V_air = 4*π*r^3 / 3
V_air = 4*π*0.24^3 / 3
V_air = 0.05790 m^3
- The density of air ( ρ_air ) is the ratio of mass of air and the volume occupied by air. Expressed as follows:
ρ_air = m_air / V_air
ρ_air = 0.009 / 0.05790
Answer: ρ_air = 0.15544 kg/m^3