Answer:
A. 48.6 W
Explanation:
A 35kg cannonball sits at rest on a flat level surface. What is the normal force exerted on the cannon ball. Use -9.8 m/s2 for acceleration due to gravity.
A. -343N
B. 44.8N
C. 25.2N
D. 343N
Answer:
a) N = 343 [N]
Explanation:
We must remember Newton's third law, which tells us that the force acting on a body is equal to the normal reaction force of equal magnitude but acting in the opposite direction.
[tex]N=m*g[/tex]
where:
m = mass = 35 [kg]
g = gravity acceleration = 9.81 [m/s²]
[tex]N = 35*9.8\\N= 343 [N][/tex]
All of the following use an electric motor, EXCEPT
A.) radio
B.) blender
C.) hair dryer
D.) electric fan
Answer:
radio
Explanation:
Answer:
radio
Explanation:
all except radio use electric motors
21. A teacher does the following:
i. walks 4 m, south
ii. walks 8 m, east
iii. walks 4 m, north
iv. walks 8 m, west.
The overall displacement of the teacher is
a. Om
b. 6 m
c. 12 m
d. ... Nonsense! It cannot be calculated without knowing time information.
Answer:
displacement is the change from a starting point. she ends up back where she started so her displacement is zero meters although she traveled 24m in all.
Chloe leads South’s varsity softball team in hitting. In a game against New Greer Academy this past weekend, Chloe slugged the 1-kg softball so hard that it cleared the outfield fence and landed on Lake Avenue. At one point in its trajectory, the ball was 19.2 m above the ground and moving with a speed of 31.6 m/s. Determine the total mechanical energy of the softball.
Answer:
it has the same mechanicals as a baseball
Explanation:
4. If you fall out of a plane and point your head down, it would take about 5 s to
reach a velocity of 49.1 m/s downward. What is the acceleration of gravity?
Answer:
acceleration due to gravity is always going to be 9.8m/s^2 whenever an object is freely falling.
Explanation:
You could also divide 49.1 m/s by 5s to get an acceleration of 9.8 m/s^2 as well.
The tree branch in the preceding problem sags, and the child's feet rest on the ground. If the tension in the rope is reduced to 220 N, what is the value of the normal force being exerted on the child's feet?
The complete question is
A 45-kg child sits on a 3.2-kg tire swing. The tension on the rope is 470 N. The tree branch sags and the child's feet rest on the ground. If the tension in the rope is reduced to 220 N, what is the value of the normal force being exerted on the child's feet?
Answer:
Therefore the Normal force is being exerted on the child's feet is 252.36( 250N).
Explanation:
We are given
mass of child = 45kg
mass of the tire = 3.2kg
g = 9.8 m/s^2
We have the first case in which the tire is in swing so tension in that case will be which is the resultant force.
Fr = Resultant force
Ft = Tension force
Fg= Gravitational force
Fr = Fg + Ft
0 = -mg + Ft
Ft = mg
= (45+3.2)*9.8
= 48.2 * 9.8
Ft = 472.36N ( which is close to 470)
In the second case the child is in the rest position, The resultant force will be zero.
Fr = Ft + Fn + Fg ( Normal force is denoted by Fn )
0 = Ft + Fn + Fg
Fn = -Fg -Ft
Fn = mg -Ft
= 472.36 - 220
Fn = 252.36N ( close to 250N)
Therefore the Normal force being exerted on the child's feet will be 252.36N.
Light that enters your eye strikes cells in the back of your eye
true
False
Answer: True
Explanation: Light enters your eye through the lens which then hits the retina which is located in the back of your eye.
HELP ASAP
The Target employees are working hard to get the orders out to everyone. The employees need to move packages from the ground level to the top of the loading dock platform. As shown in Figure 1, the employee pushes the package up a ramp (you may assume friction is negligible). In figure 2, the employee lifts the package straight up from ground to the loading dock platform. In which case does the employee do more work on the box and why?
a
Lifting the box straight up, because the incline acts as a simple machine and reduces the force required
b
Lifting the box straight up, because it requires a larger applied force to lift it straight up
c
Pushing the box up the incline, because the force is applied for a longer distance
d
Neither method, because the work is the same in both cases, since using the ramp decreases the force by the same factor that it increases the distance
Answer:
I believe the answer is B
A baseball on the Moon and an identical baseball on the Earth are thrown vertically upward with the same initial velocity of 12 m/s. The acceleration due to gravity on the Moon is 1/6 that of Earth. What is the maximum height the ball reaches on the moon? What is the maximum height the ball reaches on the earth? What is the difference in the maximum height the ball reaches on the Moon compared to on Earth?
Answer:
a. 3.68 m b. 0.61 m c. 3.07 m
Explanation:
a. What is the maximum height the ball reaches on the moon?
Using v² = u² - 2g'h where u = initial velocity of baseball = 12 m/s, v = final velocity of baseball = 0 m/s (since it stops at maximum height), g' = acceleration due to gravity on moon = g/6 where g = acceleration due to gravity on earth = 9.8 m/s², so g' = 9.8 m/s²/6 = 1.63 m/s² and h = maximum height of ball on moon.
So, making h subject of the formula, we have
h = -(v² - u²)/2g'
substituting the values of the variables, we have
h = -((0 m/s)² - (12 m/s)²)/2(1.63 m/s²)
= -(- 12 m²/s²)/2(1.63 m/s²)
= 6 m²/s²)/(1.63 m/s²)
= 3.68 m
b. What is the maximum height the ball reaches on the earth?
Using the same equation for the maximum height the baseball travels on the moon for that on the earth, the maximum height h' the baseball travels on the earth is given by
h' = -(v² - u²)/2g where u = initial velocity of baseball = 12 m/s, v = final velocity of baseball = 0 m/s (since it stops at maximum height), g = acceleration due to gravity on earth = 9.8 m/s²and h' = maximum height of ball on moon.
substituting the values of the variables, we have
h = -((0 m/s)² - (12 m/s)²)/2(9.8 m/s²)
= -(- 12 m²/s²)/2(9.8 m/s²)
= 6 m²/s²)/(9.8 m/s²)
= 0.61 m
c. What is the difference in the maximum height the ball reaches on the Moon compared to on Earth?
The difference in the maximum height the ball reaches on the Moon compared to on Earth is d = h - h' = 3.68 m - 0.61 m = 3.07 m
HI PLEASE HELP ASAP. THANK YOU
Answer:
3763.2 Joules
Explanation:
GPE = mgh
m = 120kg
g = 9.8
h = 3.2 m
GPE = (120)(9.8)(3.2)
GPE = 3763.2 Joules
A food packet is dropped from a helicopter during a flood-relief operation from a height of 750 meters. Assuming no drag (air friction), what will the velocity of the packet be when it reaches the ground?
Answer: 121.2 m/s
Explanation:
Here we will use the conservation of energy.
We can write the total energy of an object as:
E = K + U
For this particular case we have:
K = kinetic energy = (m/2)*v^2
U = potential energy = m*g*h
where:
m = mass of the object.
g = gravitational acceleration = 9.8m/s^2
h = height at which the object is dropped, in this case 750m
v = velocity of the object.
Right when the packet is dropped, it's velocity is equal to zero, this means that there is no kinetic energy and only potential energy, then we have:
Ei = Ui = m*9.8m/s^2*750m = m*(7350m^2/s^2)
And when the object is about to hit the ground, h will be almost equal to zero, this will mean that we will have only kinetic energy, and because of the conservation of energy, this final energy must be the same as the initial energy, then we will have
Ei = Ef
m*(7350m^2/s^2) = Ef = Kf
m*(7350m^2/s^2) = (m/2)*v^2
We can divide by m in both sides to get:
(7350m^2/s^2) = (1/2)*v^2
√( 2*(7350m^2/s^2)) = v = 121.2 m/s
Then the velocity of the packet when it reaches the ground is 121.2 m/s
A power plant to represent the need for and use for energy; label it energy production.
1. What is diffraction?
2.Give an example of diffraction.
Answer: a process which a beam of light spread out as a result of the passing through a narrow aperture
Explanation:
Gravity affects atmospheric pressure true or false
Answer:
false
Explanation:
The sound intensity level at a seat that is a distance of 2.00 meters from a rock concert stage is 120 dB. (a) Calculate the Intensity, I1 , of the sound in W/m2 at that position. (b) Calculate the sound level in dB at a seat that is 32 meters from the stage, given that the intensity decreases with the square of the distance from the source.
Answer:
[tex]1\ \text{W/m}^2[/tex]
[tex]0.0039\ \text{W/m}^2[/tex]
Explanation:
[tex]I_1[/tex] = Intensity of sound at 2 m away
Sound level = 120 dB
[tex]r_1[/tex] = 2 m
[tex]r_2[/tex] = 32 m
[tex]I_0[/tex] = Threshold of sound = [tex]10^{-12}\ \text{W/m}^2[/tex]
Sound level is given by
[tex]dB=10\log (\dfrac{I_1}{I_0})\\\Rightarrow I_1=10^{\dfrac{dB}{10}}I_0\\\Rightarrow I_1=10^{\dfrac{120}{10}}\times 10^{-12}\\\Rightarrow I_1=1\ \text{W/m}^2[/tex]
The intensity of sound at 2 m away is [tex]1\ \text{W/m}^2[/tex]
[tex]I_1=\dfrac{P}{4\pi r^2}[/tex]
[tex]I\propto \dfrac{1}{r^2}[/tex]
[tex]\dfrac{I_1}{I_2}=\dfrac{r_2^2}{r_1^2}\\\Rightarrow I_2=\dfrac{I_1r_1^2}{r_2^2}\\\Rightarrow I_2=\dfrac{1\times 2^2}{32^2}\\\Rightarrow I_2=0.0039\ \text{W/m}^2[/tex]
The intensity of the sound 32 m away is [tex]0.0039\ \text{W/m}^2[/tex]
_______________ is the name for the permanent destruction and clearing of forests
Answer:
DeforestationExplanation:
__________________________________________________________
According to Vocal Media,
__________________________________________________________
Deforestation is the permanent destruction of forests in order to utilize the land or trees. Typically, deforestation is clearing a lot of trees without the intention of establishing future growth. Harvesting, forest fires, and insect infestations do not count as deforestation because the affected areas will eventually grow back.
__________________________________________________________
Hope this helps! <3
__________________________________________________________
An astronaut in the space shuttle is orbiting the earth at an altitude of 2.982 x 10^5 m. He sends a radio transmission to a receiving antenna directly below him on the earth. What is the time delay between the time he sends his signal and when the receiving antenna on the earth picks it up?
Form hypothesis: How do you think increasing the resistance in a circuit will affect the current in the wire? (format: if, then, because)
Answer:it would make it thicker
Explanation:
Answer:
"The equation shows that the current in a circuit is inversely proportional to the resistance of the circuit. An increase in resistance would result in a decrease in current. And the factor by which the resistance increases is the same factor by which the current decreases."
Explanation:
Because it's just like wearing a glove/mitten when getting something out of the oven, because of the insulation from the glove/mitten, it reduces the heat that gets through into your hand, and it protects it. Just like what the "answer" says, it said that the resistance would decrease current.
which object is completely opaque?
a:wooden spoon
b: drinking glass
c: wax paper
d:window
Answer:
a
Explanation:
light can not pass through it completely
An electric current consists of moving
A) atoms
B) electrons
C) elements
D) molecules
A) atoms
B) electronsC) elements
D) molecules
Any one their to help
A popular ride at an amusment park lifts
customers up to a height of 50 m and then
drops them threw a displacement of 50 m
before slowing them to a stop. How fast
are the customers going at the 50 m
mark?
Answer:
five dollars
Explanation:
im thick lol
A person pours some chlorine bleach into a clothes washer to remove stains from the clothing. What is one chemical property or the bleach?
A. It’s density
B. It’s mass
C. It’s color
D. It’s pH
One chemical property of the bleach is its pH.
What is pH?This is referred to as the power of hydrogen and is a measure of how acidic/basic a substance is.
pH is an example of chemical property because it's associated with a change in its chemical composition. This thereby makes option D the most appropriate choice.
Read more about pH here https://brainly.com/question/4137247
Answer: It's pH
Explanation: I took the test
Janet jumps horizontally off a high diving platform with a velocity of 2.76 m/s and lands in the water 2.3 s later. How high is the platform? The acceleration of gravity is 9.8 m/s. Answer in units of m.
How far from the base of the platform does she land? Answer and units of m.
Answer:
(a) Let the height of the platform is h meter,
=>By s = ut + 1/2gt^2
=>h = 0 + 1/2 x 9.8 x (2.3)^2
=>h = 25.92 m
(b) By R = [Ux] x t
=>R = 2.47 x 2.3
=>R = 5.68 m
Explanation:
Explanation:
From the exercise we know the initial horizontal velocity and the time that Janet takes to land in the water
a) Knowing the formula for free falling objects, we can calculate how high is the platform
At t=2.3m the position of Janet is y=0m
So, the platform is 26m tall
b) According to dynamics the displacement of an object can be analyze using the following formula:
So, Janet lands 6 m far from the base of the platform
A student named Bob is on a bike and the mass is 50 kg. The force causes the student to accelerate at 3 m/s to the power of 2. Calculate the net force that causes this acceleration.???
Answer:
150 N
Explanation:
Force is equal to mass times acceleration. 50 kg accelerating at a mass of 3m/3² is undergoing a force of 150 m/s², or 150 Newtons
an astronaut has a mass of 150 kg on earth. what would be the mass of the astronaut on the moon.
Answer:
Weight On the Moon: 24.80 kilograms
Ronald observes a large island off the coast of Indonesia on a map. A few months later, he observes that there are many smaller islands in place of the large one he had seen earlier. Which of these could have caused this change?
Answer:
idgaf
Explanation:
lol
Which of these is not a method of preventing the corrosion of metals?
A) galvanising
B) painting
C) plating
D) rusting
Answer:
D
Explanation:
rusting is actually the corrosion of metals so it can't be a way to prevent itself.
____________ is renewable energy source captured using the heat of the Earth.
Answer:
geothermal energy is the answer
If the person's velocity is changing is the person
accelerating
Answer:
a change in velocity can be a change in magnitude (or speed), but it can also be a change in direction.
A soccer player kicks a ball 6.5 meters. How much time is needed for the ball to travel this distance if its velocity is 22 meters per second?
. . .
. . .
. . .
!
.
Your answer is 0.30 seconds
