Answer:
P=F/A
Explanation:
P. Is pressure
F is force
A is area
A student did 24 J of work on a chair. She applied a force of 12 N and moved the chair 2 m. What question do you need to ask to determine the amount of power used?
Answer:
Explanation:
Power is expressed as P = Force * Distance/time
From the formula given, the following parameters is needed to calculate power
1) Work done
2) force
3) Distance
4) Time
From the question, the given data is incomplete. We are supposed to be given the time taken to moved the chair over the distance. with the time we can easily calculate the power used up by the student.
4. Maria wondered if different colors (red, orange, yellow, green, blue, and purple) of plastic wrap affected the time for bread to mold. She also wrapped a slices of bread in clear plastic wrap to see how they may normally mold. Before wrapping the same type of bread (Wonder Whole Wheat), she placed 5 ml of water in the center of each slice. The slices were of the same size and wrapped in the same manner and kept in a dark space at 75 degrees Fahrenheit. She measured the area of mold growth for one week after the mold first appeared. She observed 25 slices of bread for each color of wrap and the clear wrap as well. what is the constant variable the independant variable and the depentant variable
Answer:
Constant variable: SAME TYPE OF BREAD (Wonder whole wheat), SAME AMOUNT OF WATER (5ml), SAME SIZE OF BREAD SLICE, SAME TEMPERATURE (75°F)
Independant variable: COLORS OF PLASTIC WRAP
Depentant variable: TIME FOR BREAD TO MOLD
Explanation:
In any experiment, the independent variable is the variable that is deliberately changed or manipulated by the experimenter. In this case, the independent variable is the DIFFERENT COLORS OF PLASTIC WRAP USED (red, orange, yellow, green, blue, and purple).
Dependent variable is the variable that the experimenter measures in an experiment. It is the variable that responds to changes made to the independent variable. In this experiment, the dependent variable is the TIME IT TAKES FOR BREAD TO MOLD.
Constant variable, also known as Controlled variable, is the variable that the experimenter keeps constant or unchanged for all groups throughout the experiment. In this experiment, the constants are: SAME TYPE OF BREAD (Wonder whole wheat), SAME AMOUNT OF WATER (5ml), SAME SIZE OF BREAD SLICE, SAME TEMPERATURE (75°F)
You stand on a pier watching water waves and see 10.9 waves pass by in a time of 28 seconds. What is the frequency of the water waves?
Answer:
0.4Hz
Explanation:
Given parameters:
Number of waves = 10.9waves
Time taken = 28s
Unknown:
Frequency of water waves = ?
Solution:
The frequency of a wave is the number of waves that passes through a point per unit of time.
Frequency = [tex]\frac{number of waves }{time}[/tex]
Insert parameters and solve;
Frequency = [tex]\frac{10.9}{28}[/tex] = 0.4Hz
Calculate the acceleration of a 300,000-kg jumbo jet just before takeoff when the thrust on the aircraft is
120,000n
I
Answer:
0.4 m/s²
Explanation:
Use Newton's second law.
∑F = ma
120,000 N = (300,000 kg) a
a = 0.4 m/s²
At what point does the rollercoaster have the most GPE? A,C B,A C,E D,B E,D
Answer:
b
Explanation:
What are some immediate effects that alcohol have on people?
Answer:
Depending on how much is taken and the physical condition of the individual, alcohol can cause:
-Slurred speech.
-Drowsiness.
-Vomiting.
-Diarrhea.
-Upset stomach.
-Headaches.
-Breathing difficulties.
-Distorted vision and hearing.
Explanation:
Help! Need answers for #1-5.
some benefits of driver less cars
Benefits of Driverless Cars:
Reduced pollution and emissionsIncrease in road safety resulting in fewer accidentsImproved fuel economyLower fuel consumptionReduced trafficReduced travel time and transportation costsMore accessibility for those that can't driveLane capacity is increaseda car is driving down a road in the early morning when a deer walks into the road. if the deer was 25 meters away when the driver noticed it and the car was traveling 20m/s, did the car strike the deer?
Answer:
For the car not to strike the deer, the minimum deceleration should be 8 m/s² with a combined instantaneous drivers reaction
Therefore, weather the deer is struck by the car depends on the drivers reaction time and deceleration of the car
Explanation:
The given parameters are;
The distance away from the deer the car was when the driver notices the deer = 25 m
The speed of the car = 20 m/s
Therefore, for the car not to strike the deer, the minimum deceleration of the car should be from 20²/(2 × 25) = 8 m/s² for an instantaneous driver reaction time
For a driver reaction time of 0.5 seconds, we have
Distance moved by car = 0.5 × 20 = 10 meters
Distance of the car from the deer at the start of deceleration = 25 - 10 = 15 meters
Minimum deceleration of the car required = 20²/(2 × 15) = 13.[tex]\bar 3[/tex] m/s²
For the car not to hit the deer, the minimum deceleration should be 8 m/s² with instantaneous driver's reaction.
Car hit the deer will depend on the driver's reaction time and deceleration of the car,
Given here,
Distance, when driver notice the deer = 25 m
Speed of the car = 20 m/s
So, the minimum deceleration
[tex]\bold {= \dfrac {20^2 }{2\times 25} = 8\ m/s^2 }[/tex]
Therefore, for the car not to strike the deer, the minimum deceleration of the car should be 8 m/s² with an instantaneous driver reaction time.
To know more about decceleration,
https://brainly.com/question/4403243
A block hangs from the ceiling by a spring. What are the forces acting on the block (assume the block is not moving). Choose all that apply.
A ball is thrown straight up in the air with a velocity of 12 m/s. Find the maximum height the ball reaches.
Show your work
Answer:
7.35 m
Explanation:
We can solve with kinematics or with energy.
Using kinematics, given:
v₀ = 12 m/s
v = 0 m/s
a = -9.8 m/s²
Find: Δy
v² = v₀² + 2aΔy
(0 m/s)² = (12 m/s)² + 2 (-9.8 m/s²) Δy
Δy = 7.35 m
Using energy instead:
PE = KE
mgh = ½ mv²
gh = ½ v²
h = v² / (2g)
h = (12 m/s)² / (2 × 9.8 m/s²)
h = 7.35 m
a motor with an efficiency of 75 percent must supply 240J of useful work. what amount of work must be supplied to the motor
Answer:
e=75%=0.75 work output = usful work=240j
Explanation:
A stone is thrown horizontally from the top of a 25.00-m cliff. The stone lands at a distance of
40.00 m from the edge of the cliff. What is the initial horizontal velocity of the stone?
The projectiles launch allows to find the answer for the initial velocity of the stone is:
v = 17.71 m / s
Projectile launching is an application of kinematics for motion in two dimensions, where there is no acceleration on the x axis and the acceleration on the y axis is the gravity acceleration.
In the attached diagram we can see a corner of the movement. Where the x axis is horizontal and the y axis is vertical, where the zero of the system is at the base of the cliff
In this case the stone is thrown horizontally, therefore its initial vertical speed is zero, let's find the time it takes to reach the base of the cliff
y = y₀ + [tex]v_{oy}[/tex] t - ½ g t²
where y and y₀ are the current and initial position, [tex]v_{oy}[/tex] is the initial vertical velocity, g the acceleration of gravity and t the time
When reaching the bottom its height is zero (y = 0) and the highest part its initial height is y₀ = 25.00 m
0 =y₀ + 0 - ½ g t²
t = [tex]\sqrt{\frac{2y_o}{g} }[/tex]
Let'se calculate
[tex]t = \sqrt{ \frac{2 \ 2.25 }{9.8 } }[/tex]
t = 2,259 s
They indicate that the stone fell at a horizontal distance of 40 m,
x = [tex]v_{ox}[/tex] t
v_{ox} = [tex]\frac{x}{t}[/tex]
v_{ox} = [tex]\frac{40}{2.259}[/tex]
v_{ox} = 17.71 m / s
In conclusion, using theprojectiles launch we can find the answer for the initial velocity of the stone is:
v = 17.71 m / s
Learn more here: brainly.com/question/12792922
HELP PLEASE ASAP, 10 POINTS!
Answer:
2 is answer B.
3 is answer D.
3 is answer D because of the fears as to what happened with Chernobyl.
I hope this helps.
No matter where the light bulb is located on the central axis, what is always true about the size of the image?
Answer:
there is no image
Explanation:
Using terms like GPE, KE, Transfer, Transfermation and Law of Conservation of Energy. Will a ball placeced at the start arrow and allowed to roll make it to the finish arrow? Why?
A boy climbs to the roof of his house and throws a rock at a horizontal velocity of 11.5 m/s. The rock lands on the ground, 15.3 m from the base of the house. How high is the roof of the house?
Answer:
The roof of the house is 8.67 m high
Explanation:
Horizontal Motion
When an object is thrown horizontally with a speed v from a height h, the range or maximum horizontal distance traveled by the object can be calculated as follows:
[tex]\displaystyle d=v\cdot\sqrt{\frac {2h}{g}}[/tex]
The boy is on the roof of his house and throws a rock horizontally at v=11.5 m/s. It lands on the ground d=15.3 m from the base of the house. We can use the above equation to find the height of the roof by solving it by h:
[tex]\displaystyle h=\frac{gd^2}{2v^2}[/tex]
Substituting values:
[tex]\displaystyle h=\frac{9.8\cdot 15.3^2}{2\cdot 11.5^2}[/tex]
h=8.67 m
The roof of the house is 8.67 m high
2 points
If a break-dancer lies down on the ground on his back, his force of 635 N
is spread over an area of 0.75 m2. How much pressure does he exert on
the ground in this position? *
ws
846.7 Pa
O 84.7Pa
O 8.467 Pa
8467.7 Pa
Answer:
846.7Pa
Explanation:
Given parameters:
Force = 635N
Area = 0.75m²
Unknown:
Pressure = ?
Solution:
Pressure is the force per unit area on a body.
Pressure = [tex]\frac{Force}{Area}[/tex]
Insert the parameters and solve;
Pressure = [tex]\frac{635}{0.75}[/tex] = 846.7Pa
Which of the following accurately describes how a magnetic motor works
a
A set of electric coils are placed in a magnetic field. When a current passes through the wire, it creates a reaction that causes the atoms to being to shift into place
b
A set of electric coils are placed in a magnetic field. When a current passes through them, they create a magnetic field which interacts with the first magnetic field, causing the set of coils to rotate
c
A set of magnets are placed in an electric field. As the current increases or decreases, the strength of the electric field changes, causing the magnet to be more or less moved by the field
d
A set of magnets are placed in an electric field. A current is run through the magnets, thus increasing their magnetic fields. Once the magnetic field is increased, the magnets can be manipulated by the electric field by being guided around
Answer:
The correct option is;
c. A set of magnets are placed in an electric field. As the current increases or decreases, the strength of the electric field changes, causing the magnet to be more or less moved by the field
Explanation:
A permanent magnet motor is an electric motor that utilizes permanent magnets combined with a coil of electric wire winding rather than there being only the the electric wire windings in the motor
The principle of operation of a permanent magnet motor involves the rotation of a magnetic rotor by the electromagnetic force generated from the outer stator coil when power is supplied to the stator windings from an external source.
What happens to energy when elastic objects interact with other objects?
2. Marta was biking along the bike path at an average velocity of +4.2 m/s. If she biked for 800 seconds,
how far did she travel? (4 pts)
Answer:
3360m
Explanation:
Given parameters:
Average velocity of Marta = 4.2m/s
Time taken for biking = 800s
Unknown:
Distance traveled =?
Solution:
Velocity is the rate of change of displacement with time.
Displacement = velocity x time
Input the parameters and solve;
Displacement = 4.2 x 800 = 3360m
A student observes an 8.0-kilogram shopping cart accelerate uniformly across a parking lot. It reaches a speed of 4.0 meters per second in 0.5 seconds. What is the magnitude of the force that causes the shopping cart to accelerate?
Answer:
F = 64 N
Explanation:
Given that,
Mass of the shopping cart, m = 8 kg
Initial speed of the shopping cart, u = 0
Final speed of the shopping cart, v = 4 m/s
Time, t = 0.5 s
We need to find the magnitude of the force that causes the shopping cart to accelerate. The force is given by the formula as follows :
[tex]F=ma\\\\F=\dfrac{m(v-u)}{t}\\\\F=\dfrac{8\times (4-0)}{0.5}\\\\F=64\ N[/tex]
So, the magnitude of force is 64 N.
A person walks 200meters at 27 degrees north of East
Answer:
sdf
Explanation:
6.
How long would it take a 125 W electric motor to do 825 j of work?
Answer:
According to formula of power N = A/t Given by : N = 125 W and A = 825 J.
Here, N --- power ; A --- work ; t --- time.
Now, we can find the time t = A/N = 6.6 s
Explanation:
A hockey puck with a mass of 0.17 kg is traveling to the right along the ice at 15 m/s. It strikes a second hockey puck with a mass 0.11 kg. The first hockey puck comes to rest after the collision. What is the initial momentum of the system? Round to the nearest tenth.
Answer: 2.6
Explanation: Just trust me...
An object, initially traveling at a velocity of 52 m/s, experiences an acceleration of -9.8 m/s². How much time will it take it to come to rest? *
Answer:
5.3 s
Explanation:
Given:
v₀ = 52 m/s
v = 0 m/s
a = -9.8 m/s²
Find: t
v = at + v₀
0 m/s = (-9.8 m/s²) t + 52 m/s
t = 5.3 s
Explain the relationship between temperature, density, and states of
matter
Answer:
Higher temperature makes an object less dense 2. Density governs the state of matter for the object, hence as water becomes less and less dense, it becomes gas (water vapour) 3. Higher temperature makes an object has more pressure, hotter gas has higher pressure.
Explanation:
Relation Between Density and Temperature Temperature is the measure of heat. Density is the measure of how closely any given entity is packed or it is the ratio of the mass of the entity to its volume.
I hope this works
6. _____ When the nuclei of lighter atoms are combined to make heavier atoms: a. Nuclear Fusion b. Nuclear Fission c. Chemical Energy d. Atomic Bombs
Answer: The correct option is A.
Nuclear fusion.
Explanation:
It is nuclear fussion because nuclear fussion is the process whereby two or more lighter atomic nuclei come together that the forces that pull them together surpasses the forces that might pull them away making them to combine together to form heavier atomic nuclei. Energy is released in nuclear fusion.
i will give u brainliest!
The answer is C. Hope this helps!
A geologist has collected this data about the rock ages in a certain area.
If generating a key for this data, what is the correct sequence from bottom to top?
a. C A B D E
Selected:b. E D B A CThis answer is incorrect.
c. E D C B A
d. A B C D E
Answer:
C A B D E
Explanation:
The newest rocks are always on top, and the oldest rocks are on the bottom.
C. 305 million
A. 200 million
B. 68 million
D. 3 million
E. 800 thousand