Answer:
The answer is Control Variable.
2. How far does a car travel in 90 seconds if it is traveling at a speed of 55 m/s?
Answer:
distance = speed × time
= 55m/s × 90s
= 4950 m
A person is pulled to the right on a sled (total mass of 52.9 kg) across the surface of a frozen pond with a force of 67.7 Newtons so that they move with a constant velocity. What is the force of friction acting on the sled?
Answer:
67.7 N
Explanation:
Draw a free body diagram of the person on the sled. There are four forces:
67.7 N to the right,
friction force to the left,
weight force down,
and normal force up.
Constant velocity means 0 acceleration.
Sum of the forces in the x direction:
∑F = ma
67.7 N − F = 0
F = 67.7 N
To calculate the density of an object, which of the following values do you
need to know?
A. Volume
B. Buoyancy
C. Weight
D. Mass
Answer:
Volume I think
Explanation:
Answer:
A. volume and D. mass
Explanation:
Density is the amount of matter (mass) in a given space (volume).
The density of an object can be found using the following formula:
d=m/v
where m is the mass and v is the volume.
In order to find the density, you must know the mass and the volume of the object.
Therefore, the correct answers are A. volume and D. mass.
The equation for distance is d = st. How far does a car go in 10 seconds at a
speed of 44 m/s?
Answer:
44(speed) x 10(time) = 440(distance). So the answer is 440 meters.
Jack travelled 360 km at an average speed of 80 km/h. Elaine
took 1.5 hours more to complete the same amount of distance.
What was Elaine's average speed for the whole journey?
km/h
Answer:
Average speed of Elain = 60 km/h
Explanation:
Total Distance covered by Jack = 360km
Average Speed of Jack = 80 km/h
Time taken by Jack to complete his journey = Distance / Average speed = 360 km / 80 km/h
Time taken by Jack to complete his journey = 4.5 hours
As it is given the both Jack and Elain travelled the same amount of distance:
Total distance travelled by Elain = 360 km
It is given that Elain took 1.5 hourse more than Jack to cover the distance, so Time taken by Elain to cover the distance is = 4.5 hours + 1.5 hours = 6 hours
Average speed of Elain = Distance/ time = 360 km / 6 hours
Average speed of Elain = 60 km/h
why do you think the moon appears to change shape as it revolves around the earth?
bumper car A (281 kg) moving +2.82 m/s makes an elastic collision with bumper car B (209 kg) moving +1.72 m/s what is the velocity of car A after the collision (unit = m/s) remember: right is (+), left is (-)
Answer: V1 = 3.559 - 0.744V2
Explanation: Given that the
bumper car A has
Mass M1 = (281 kg) moving with
Velocity U1 = 2.82 m/s
bumper car B has
Mass M2 = (209 kg) moving with
Velocity U2 = 1.72 m/s
Where U1, U2 are the initial velocity of the two cars
Since the collision is elastic, we will use the formula below,
M1U1 + M2U2 = M1V1 + M2V2
Substitute the values into the formula
281×2.28 + 209×1.72 = 281V1 + 209V2
640.68 + 359.48 = 281V1 + 209V2
1000.16 = 281V1 + 209V2
Make V1 the subject of formula
281V1 = 1000.16 - 209V2
V1 = 1000.16/281 - 209V2/281
V1 = 3.559 - 0.744V2
Therefore, the velocity of car A which
is V1 after the collision will be expressed as V1 = 3.559 - 0.744V2
Which converts mechanical energy to electrical energy?
A. A flashlight
B. An electric motor
C. A generator
D. An electromagnet
Answer:
c. A Generator
Explanation:
The whole point of a generator is to produce electrical energy. The generator will use a mechanical motor usually running off of gas to produce electricity.
Land masses that move on Earth are called: a. Continents b. Tectonic continents c. Tectonic plates d. Rock Masses HELP
Answer:
c. tectonic plates
Explanation:
Answer:
the answer is rock masses
A ball held 2.0 meters above the floor has 59 joules of potential energy the bald mass is about
Answer:
Mass of ball = 3.0102 Kg.
Explanation:
Potential energy at height h is given by
PE = mgh
where m is the mass of the body
g is the the acceleration due to gravity whose value is 9.8 m/s^2
h is the height from surface level
PE is potential energy
In the problem given h = 2 meters
PE = 59 joules
59 = m*9.8*2
=> m = 59/9.8*2 = 3.0102 Kg
Thus, mass of ball is 3.0102 Kg.
Answer:
3
Explanation:
Top person is wrong
just did lesson
what is the numerical value in meters per second squared of the acceleration of an object experiencing true free fall
Answer:
9.8m/s²
Explanation:
An object experiening a free fall is simply under the influence of gravity.
When an object is influenced by gravity, the object falls with an acceleration known as acceleration due to gravity.
This acceleration known as acceleration due to gravity has a constant value of 9.8m/s².
give one reason why the energy carries bu sound waves decreases as those sound waves travel through air
List the 2 advantages and 2 disadvantages of wind as a source of electricity.
Answer:
The first 2 advantages of wind a source of electricity is that it provides you wifi and wind. 2 disadvantages of wind as a source of electricity is that to much wind could knock it down or slow down the source of the electricity.
Explanation:
I know this because i read a article on it.
The strong nuclear force is ?
Answer: Option B
Explanation:
The nuclear force is the strongest force in the universe. It is much more stronger than all the other forces and is 100 times stronger than the electric force.
The nuclear forces can be defined as the forces generated due to electron and protons in which the electrons have negative charge on it and the protons have positive charge on it.
Due to this force all the atoms and molecules, elements and compounds are held together.
A car has a speed of 2 m/s and a mass of 1500 kg. What is the cars kinetic energy?
A. 4500 J
B. 3000 J
C. 1500 J
D. 6000 J
Answer:
B
Explanation:
E = mv² / 2
E = (1500kg)(2 m/s)² / 2
E = 6000 J / 2
E = 3000 J
Answer:
B
Explanation: The answer is B because the defining equation for kinetic energy is E=mv^2 / 2
e = (1500kg)(2 m/s)^2 / 2
e = 6000 J / 2
e = 3000 J = 3000 Joules
Which term is the product of force and distance? A) power B) work C) net force D) acceleration
Answer:
B. Work
Explanation:
I took the test! (e2020)
Have an awesome day!
The term is the product of force and distance is work. Therefore, option B is correct.
What is work ?Work is defined as the energy that is applied to or removed from an object by applying force along a displacement. For a constant force acting in the same direction as the motion, the work is simply equal to the product of the force's magnitude and the distance traveled.
Work and energy differ greatly from one another. Work is the transmission of energy over a specific distance in one direction with the aid of a force.
Three categories can be used to classify the type of labor performed. Positive work, negative work, and zero work are the three types. The angle between force and displacement determines the kind of work that is done.
Thus, option B is correct.
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if san andreas fault slips 2.5 cm each year how far would it separate in 100 years
Answer:
250cm or 2.5m
Explanation:
using direct variation
the length is = l
the time (year) = t
let k be the constant
so he have:
l=kt
2.5=k× 1
k= 2.5
Now in the next statement the 100 is given but not the length so
l=kt
~ l=k× 100 years
But k = 2.5
so :
l= 2.5×100
l= 250 cm
Hence it will be 250cm or 2.5m at which they will get separated
(4A) The mass of Earth is 5.972 * 10^24 kg, and the radius of Earth is 6,371 km.
The mass of the moon is 7.348 * 10^22 kg, and the radius of the moon is 1,737
km. The centers of the Earth and the moon are separated by 384,400 km. If an
object is traveling from Earth to the moon along the line connecting the center
of Earth and the center of the moon, at what distance from the center of Earth
will the net force on the object due to the gravitational attractions of Earth and
the moon be zero?
Answer:
x₁ = 345100 km
Explanation:
The direction of the attraction forces between the earth and the object, and between the moon and the object, are in opposite direction and (along the straight line between the centers of earth and moon) and as gravity is always attractive, the net force will become zero when both forces are equal. According to this:
Let call "x₁" distance between center of the earth and the object, and
"x₂" the distance between center of the moon and the object, Mt mass of the earth, Ml mass of the moon, m₀ mass of the object
we can express:
F₁ ( force between earth and the object )
F₁ = K * Mt * m₀/ ( x₁)² K is a gravitational constant
F₂ (force between mn and the object)
F₂ = K * Ml * m₀ / (x₂)²
Then:
F₁ = F₂ K*Mt*m₀ / x₁² = K*Ml*m₀ /x₂²
Or simplifying the expression
Mt/ x₁² = Ml/ x₂²
We know that x₁ + x₂ = 384000 Km then
x₁ = 384000 - x₂
Mt/( 384000 - x₂)² = Ml / x₂²
Mt * x₂² = Ml *( 384000 - x₂)²
We need to solve for x₂
Mt * x₂² = Ml *[ ( 384000)² + x₂² - 768000*x₂]
By substitution:
5.972*10∧24*x₂² = 7.348*10∧22 * [ 1.47*10∧11 ] + 7.348*10∧22*x₂² -
7.348*10∧22*768000*x₂
Simplifying by 10∧22
5.972*10²*x₂² = 7.348* [ 1.47*10∧11 ] + 7.348*x₂²- 7.348*768000*x₂
Sorting out
5.972*10²*x₂²- 7.348*x₂² = 10.80*10∧11 - 56,43* 10∧5*x₂
(597,2 - 7,348 )* x₂² = 10.80*10∧11 - 56.43*10∧5*x₂
590x₂² + 56.43*10∧5*x₂ - 10.80*10∧11 = 0
Is a second degree equation
x₂ = -56.43*10∧5 ± √3184*10∧10 + 25488*10∧11 / 1160
x₂ ₁ = -56.43*10∧5 + √3184*10∧10 + 25488*10∧11 / 1160
x₂ ₁ = -56.43*10∧5 + √3184*10∧10 + 254880*10∧10 / 1160
x₂ ₁ = -56.43*10∧5 + 10∧5 [ √3184 + 254880 ] /1160
x₂ ₁ = -56.43*10∧5 + 508* 10∧5 / 1160
x₂ ₁ = 451.27*10∧5/1160
x₂ ₁ = 4512.7*10∧4 /1160
x₂ ₁ = 3.89*10∧4 km (distance between the moon and the object)
x₂ ₁ = 38900 km
x₂ = 38900 km
We dismiss the other solution because is negative and there is not a negative distance
Then the distance between the earth and the object is:
x₁ = 384000 - x₂
x₁ = 384000 - 38900
x₁ = 345100 km
Liz has designed a sailboat. She wants to build a prototype of the boat. Liz has $12,000 to spend on the boat. $7,000 of that money is budgeted for wood. Liz needs 500 ft of wood planks.
Assuming that Liz will use only one type of wood for her entire project, which of the following could she use to stay on budget?
A. Marine plywood only.
B. She could use any of these woods listed.
C. Marine plywood of Douglas for only.
D. Marine plywood, Douglas fir, or white oak only
Answer:
A. Marine plywood only.
Explanation:
Explain how reflection and refraction are similar to each other and different from each other.
Answer:
Reflection is the bouncing back off light rays when it hits a surface whilst refraction is the change in direction if light as it travels from one medium to another.They both need a medium or surface to be able to work
Explanation:
When a wave that is moving through a medium encounters the border of that medium, reflection and refraction, both wave characteristics, take place.
Both refraction and reflection alter the wave's behavior by altering the direction it travels in or the rate at which it moves.
What is Refraction?Refraction is the process by which a wave switches while transitioning from one material to another in physics. As an illustration, waves move more quickly in the open ocean than those in the shallow.
A wave can swing around until it is moving perpendicular to the coastline if it is approaching a beach at an angle because the wave's outer portion goes quicker than its inner portion.
When light strikes a material on a plane, reflection occurs, which is when the light bounces back. Refraction is indeed the technique by which light's path changes when it passes through a substance, bending the light.
This is the primary distinction between refraction and reflection. Usually, mirrors are where this occurrence happens.
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if earth were not tilted, would we still have seasons?
Answer:
Glad you asked that!
Explanation:
Actually,no.You see,if the earth was perfectly straight,then the northern hemisphere and southern hemisphere would have the same seasons,which is pretty much the world.But our world is tilted,so we happen to have differences for southern hemisphere and northern hemisphere.
Jack rolled a marble down a ramp and recorded the potential energy and kinetic energy of the marble at different positions on the ramp, as shown in the table. Marble experiment Height of Marble from Ground (meters) Potential Energy of Marble (Joules) Kinetic Energy of Marble (Joules) Total Energy of Marble (Joules) Trial 1 1 1 3 4 Trial 2 2 3 1 4 Which is the independent variable in this experiment? Mass of marble Kinetic energy of marble Potential energy of marble Height of marble from ground
Answer: D
Height of marble from ground
Explanation:
From the formula of kinetic energy and potential energy,
K.E = 1/2mv^2
While
P.E = mgh
From all the parameters given from the question. You can see that mass is constant, acceleration due to gravity is also constant.
Independent variable must be a value that can varies.
Since Jack rolled a marble down a ramp and recorded the potential energy and kinetic energy of the marble at different positions on the ramp to see the effects on both energies.
This different position must be the height which will produce an effect on the potential and kinetic energy of the marble.
Independent variable always provides an effect for dependent variable. Which are kinetic energy and potential energy in this case.
Height of marble from ground is the right answer.
Answer:
The Correct Answer is D
Height of marble from ground
Explanation:
What is the inverse tangent of 0.9?
O A. 64.2
O B. 90.0
O C. 42.0
O D. 0.016°
Answer:
i think the aswers is C,
A 200 kg roller coaster car is located at the top of a hill where the height is 30 m. What is the velocity when it reaches the bottom of the hill? 5.5 m/s 11.2 m/s 16.7 m/s 24.2 m/s
Answer: 24.2
Explanation:
Answer:
24.2 m/s
Explanation:
Which best describes the act of using senses or tools to gather information?
ОООО
creating a hypothesis
making an observation
summarizing the results
recording the measurements
Answer:
Making an observation
Explanation:
By observing, you can draw qualitative and quantitative data from the subject of observation
Which of the following is a difference between a law and a theory? A law can become a theory but a theory can never become a law. A theory is based on personal feelings but a law is based on testable evidence. A theory can predict the occurrence of a natural event with certainty but a law cannot. A law is usually a mathematical statement but a theory is a proposed statement.
Answer:
a theory is based on personal feelings but a law is based on testable evidence because a law is universal and constant fact of nature it is also an irrefutable theory a theory can become a law but a law can never become a theory it is based several scientific experimenrs
Explanation:
i hope this will help you
Which statement best compares the accelerations of two objects in free fall?
O The heavier object has a greater acceleration.
O The object that has the greater surface area has the lower acceleration,
The object that has the smaller mass has the greater acceleration.
O The objects have the same acceleration
Answer:
C. The object that has the smaller mass has the greater acceleration.
Explanation:
Two objects in free fall are accelerated due to gravity.
According to Newton's second law, if two objects with different masses have same force, then object with light or smaller weight will fall with greater acceleration while the object with greater mass will fall with less acceleration.
Hence, the correct option is C.
Answer:
c
Explanation:
its c
How do Newton's laws of motion explain why it is important to keep the ice smooth on a hockey rink so that players can
pass a puck as quickly as possible?
OSmooth ice reduces the inertia of the hockey puck.
Smooth ice increases the force used to accelerate the hockey puck.
Smooth ice reduces the unbalanced forces that would slow the hockey puck.
Smooth ice decreases the reaction force that the ice exerts on the hockey puck.
Save and Fxit
Answer:
c
Explanation:
edge 2021
Antifreeze is a "must have" in an Albertan winter because it helps keep your vehicle engine from freezing in cold temperatures. Products such as antifreeze are composed of organic compounds that are classified as
a. alcohols
b. Esters
c. Carboxylic acids
d. Halogenated hydrocarbons
Products such as antifreeze are composed of organic compounds that are classified as alcohols. (a)
Maybe those other classes of chemicals also lower the freezing temperature of water, just like alcohol does. I don't know. But alcohol is what's used to make anti-freeze. I'm guessing alcohol must be cheaper, less toxic, and less corrosive inside the engines' cooling systems than any of that other stuff is.
in an elastic collision, both the momentum and the kinetic energy of the system are conserved. Identify which scenario describes an elastic collision.
A) A bullet is shot into a wooden block and becomes embedded (stuck)in the block
B)A girtjumps off the dock into a boat. The boat and the girl begin to move
C)Two billiards balls strike each other and bounce off moving in different directions
D)A female ice skater skates to her partner and he lifts her up. They continue to move as he holds her over his head.
Answer:
The answer is c. Two billiards balls strike each other and bounce off moving in different directions
Hope this helps