Answer:
Matter is any substance that has mass and takes up space by having volume
49. A block is pushed across a horizontal surface with a
coefficient of kinetic friction of 0.15 by applying a
150 N horizontal force.
(a) The block accelerates at the rate of 2.53 m/s2
Find the mass of the block.
(b) The block slides across a new surface while
experiencing the same applied force as before.
The block now moves with a constant speed.
What is the coefficient of kinetic friction between
the block and the new surface?
Answer:
(a) 37.5 kg
(b) 4
Explanation:
Force, F = 150 N
kinetic friction coefficient = 0.15
(a) acceleration, a = 2.53 m/s^2
According to the newton's second law
Net force = mass x acceleration
F - friction force = m a
150 - 0.15 x m g = m a
150 = m (2.53 + 0.15 x 9.8)
m = 37.5 kg
(b) As the block moves with the constant speed so the applied force becomes the friction force.
[tex]F = \mu m g \\\\150 = \mu\times 37.5\\\\\mu = 4[/tex]
The summer camps had a field trip from the campus to Fragrance Hill. They traveled at an average speed of 65 km/h in the first 2 hours. After that, traveled at another average speed of 78 km/h. If the distance between the campus and Fragrance Hill is 364 km, what was the total time for the field trip?
Answer:
Explanation:
They traveled this distance in 2 parts, essentially. Part 1 had an average speed for a certain number of hours, part 2 had an average speed for a certain number of hours, and those 2 parts taken together took them a distance of 364 km. In equation form, that looks like this:
km/hr part 1 + km/hr part 2 = 364 km
Now we need to find each part on the left side of that equation. Part 1 first:
We traveled 65 km/hr for 2 hours, so that took us
[tex]65\frac{km}{hr}*2hr[/tex] and canceling out the hour label, we have that in part 1 we got
65(2) = 130 km. Good. Now onto the second part, where our unknown is.
We traveled 78 km/hr the second part for x hours, so that took us
[tex]78\frac{km}{hr}*xhr[/tex] and canceling out the hour label, we have that in part 2 we got
78x km. Now we can fill in the main equation (the one in bold print)
130 km + 78x km = 364 km and subtracting 130 km from both sides:
78x km = 234 km and dividing by 78 km:
x = 3 hours. Part 2 took 3 hours. Part 1 took 2 hours, so the whole trip took 5 hours.
When an object is in a gravitational field, it has energy in its __________ __________ energy store.
Answer:
Gravitational potential
Explanation:
Any object that is not on the surface of the Earth, but at a height instead has potential energy. Eventually, this can become kinetic energy once the object falls.
When an object is in a gravitational field, it has energy in its gravitational potential energy store.
Question 4(Multiple Choice Worth 3 points)
(03.02 MC)
Which statement best reflects a change in weather?
Today is cloudy, but tomorrow will be clear and sunny.
The average rainfall has decreased over the past five years.
Ocean temperatures are projected to increase over time.
Glaciers are melting more rapidly now than in the past 100 years.
plzzz helpppp asap
Answer:
a is your answer.............
The mass of a brick is 2kg. Find the mass of water displaced by it when it is completely immersed in water. (Density of the bricks is 2.5 g/cm^3)
Answer:
2000g
Explanation:
volume=mass/density
=2000/2.5
=800cm³
mass=density×volume
=800×2.5
=2000g
22) How is it possible to fill medicine in a syringe?explain
I hope this helps you ^-^
when is the mass of an object if it exerts a force of 160 N and an acceleration of 8.15m/s^2
Answer:
f=ma.......m=f/a......m=20kg
The gravitational force acting on various masses is measured on different planets. Measured values for the forces acting on the corresponding masses are shown in the data table. Analyze the data and develop a method for comparing the gravitational field strengths on the different planets. Use your method to compare the gravitational field strengths, and report your conclusions.
The boiling point of water is 1000 C at sea level. The boiling point of butane is -1.50C… If we leave liquid butane in a bowl on a table in a room where the temperature is 240C, butane will
A. evaporate.
B. condense.
C. freeze.
D. melt.
Answer: If we leave liquid butane in a bowl on a table in a room where the temperature is [tex]24^{o}C[/tex], butane will evaporate.
Explanation:
A temperature at which the the liquid and gaseous phase of a substance of a substance are present in equilibrium with each other is called boiling point.
For example, the boiling point of butane is -1.5 degree Celsius.
This means that at a temperature above -1.5 degree Celsius, butane will exist is gaseous state. That is, at a temperature of 24 degree Celsius butane will evaporate.
Thus, we can conclude that if we leave liquid butane in a bowl on a table in a room where the temperature is [tex]24^{o}C[/tex], butane will evaporate.
Please help me with this...
And write all steps..
Answer:
[tex]2\frac{m}{s^2} =a[/tex]Explanation:
Use the kinematic equation.
[tex]v_{2} =v_{1} +at[/tex]This equation can be derived from [tex]f=ma[/tex], but we can just memorize, or look them up when needed as it saves us time.
Now we can plug our measurements into each variable to solve for acceleration.
[tex]18\frac{m}{s} =8\frac{m}{s} +a*5s[/tex]Subtract 8m/s from both sides.
[tex]10\frac{m}{s} =a*5s[/tex]Divide by 5 seconds. Left with acceleration in terms of [tex]\frac{m}{s^2}[/tex]
[tex]2\frac{m}{s^2} =a[/tex]HELPPPPPPPPPPP PLEASEEEEEEEEEEE
Complete this sentence. The solubility of a sample will ____________ when the size of the sample increases.
stay the same
decrease
increase
be unable to be determined
the answer is not decrease
The solubility of the sample will decrease
Which labels are correct for the regions marked? a. X: Slower in gases than liquids Y: Faster in solids than gases Z: Velocity depends on medium b. X: Faster in gases than liquids Y: Slowest in solids Z: Faster in liquids than gases c. X: Slower in solids than liquids Y: Velocity depends on medium Z: Faster in liquids than gases d. X: Velocity depends on medium Y: Fastest in gases Z: Slower in liquids than solids
Answer:
a. X: Slower in gases than liquids Y: Faster in solids than gases Z: Velocity depends on medium.
Explanation:
Speed of sound is fastest in solids. Sound waves travel more quickly in solid, than of liquid and gases. Sound waves travel most slowest in gases. Speed of sound varies significantly and it depends upon medium it is travelling through. In more rigid medium sounds velocity will be faster.
please answer quick for brainlist ; )
Answer:
The diagram assigned B
explanation:
Check the direction of the two vectors, their resultant must be in the same direction.
A basketball is shot by a player at a height of 2.0m. The initial angle was 53° above the horizontal. At the highest point, the ball was travelling 6 m/s. If he scored (the ball went through the rim that is 3.00m above the ground), what was the player's horizontal distance from the basket?
At the ball's highest point, it has no vertical velocity, so the 6 m/s is purely horizontal. A projectile's horizontal velocity does not change, which means the ball was initially thrown with speed v such that
v cos(53°) = 6 m/s ==> v = (6 m/s) sec(53°) ≈ 9.97 m/s
The player shoots the ball from a height of 2.0 m, so that the ball's horizontal and vertical positions, respectively x and y, at time t are
x = (9.97 m/s) cos(53°) t = (6 m/s) t
y = 2.0 m + (9.97 m/s) sin(53°) t - 1/2 gt ²
Find the times t for which the ball reaches a height of 3.00 m:
3.00 m = 2.0 m + (9.97 m/s) sin(53°) t - 1/2 gt ²
==> t ≈ 0.137 s or t ≈ 1.49 s
The second time is the one we care about, because it's the one for which the ball would be falling into the basket.
Now find the distance x traveled by the ball after this time:
x = (6 m/s) (1.49 s) ≈ 8.93 m
PLEASE HEEEEEEELP
Assume that the velocity of the soda bottle falling from a height of 0.8 m will be 4 m/s. Record this velocity for each mass in Table A, and use it in calculating the predicted kinetic energy of the soda bottle for the masses of 0.125 kg, 0.250 kg, 0.375 kg, and 0.500 kg using the equation: KE=1/2 mv^2 When solving for kinetic energy (KE), m is mass, and v is the speed (or velocity).
KE = (0.5) m v²
given that : v = speed of the bottle in each case = 4 m/s when m = 0.125 kg
KE = (0.5) m v² = (0.5) (0.125) (4)² = 1 J
when m = 0.250 kg KE = (0.5) m v² = (0.5) (0.250) (4)² = 2 J
when m = 0.375 kg KE = (0.5) m v² = (0.5) (0.375) (4)² = 3 J
when m = 0.0.500 kg KE = (0.5) m v² = (0.5) (0.500) (4)² = 4 J
The direction equivalent to {40° W of S} is:
A. 40 ° E of S
B. 40° W of N
C. 40° E of N
D. 50° S of W
E. 50° E of N
Answer:
c
Explanation:
Drag each label to the correct location on the image. Identify the particles and characteristics on this model of an atom.
Positively charged
Electron
Proton
Neutron
Negatively charged
Answer:
cant see picture
Explanation:
Answer:
please add picture so i can help you
Explanation:
A steel ball is released just below the surface of thick oil in a cylinder.
During the first few centimetres of travel, what is the acceleration of the ball?
A constant and equal to 10 m / s2
B constant but less than 10 m / s2
C decreasing
D increasing
Answer:
Increasing
Explanation:
I Hope it Helps
Example to measure the interval of time of a small stone dropped from 1m height.
Answer:
The time required is 0.45 s.
Explanation:
Height, h = 1 m
initial velocity, u = m/s
Let the time is t.
Use second equation of motion
[tex]h = u t + 0.5 at^2\\\\1 = 0 +0.5 \times 9.8 \times t^2\\\\t = 0.45 s[/tex]
what will be the magnitude of work if a force of 25N pulls a stone through a distance of 5m in its direction?
Explanation:
125 is your answer........
What is the volume of a cone with a height of 27 cm
and a radius of 13 cm? Round your answer to the
nearest tenth.
Use the button on your calculator to complete this
problem.
V =
cm?
Explanation:
→ Volume of cone = πr² × h/3
Here,
Radius (r) = 13 cmHeight (h) = 27 cm→ Volume of cone = π(13)² × 27/3 cm³
→ Volume of cone = 169π × 9 cm³
→ Volume of cone = 1521π cm³
→ Volume of cone = 1521 × 22/7 cm³
→ Volume of cone = 33462/7 cm³
→ Volume of cone = 4780.28 cm³
Answer:
4,778.4 is correct
Explanation:
What does the m stand for in the enthalpy equation?
Answer:
Use the formula ∆H = m x s x ∆T to solve.
Explanation:
Once you have m, the mass of your reactants, s, the specific heat of your product, and ∆T, the temperature change from your reaction, you are prepared to find the enthalpy of reaction. Simply plug your values into the formula ∆H = m x s x ∆T and multiply to solve.
satellite does not need any energy to revolve around the earth why
Answer:
An artificial satellites revolves around the earth under the influence of its gravitational force. So it does not require any energy to revolve around energy.
or maybe god:)))(
Why are simple everyday actions considered
thermodynamic reactions?
they transform energy
they destroy energy
they create energy
Answer:
They transform energy
Explanation:
thermodynamics deals with transfers of energy from one place to another and from one form to another and it's also deal with the relationship between heat and other forms of energy
If the electric force between two charges is 4.2 × 10-2 N, what would the new force be if the distance between the charges is doubled and the charge on one of the charges is tripled?
Answer:
New force = 0.063 N
Explanation:
Given that,
The electric force between two charges is[tex]4.2\times 10^{-2}\ N[/tex]
The formula for the electric force is:
[tex]F=\dfrac{kq_1q_2}{r^2}[/tex]
If the distance between the charges is doubled, r' = 2r and one of the charges is tripled, q₁' = 2q₁, q₂' = 3q₂
Put all the values,
[tex]F'=\dfrac{kq_1'q_2'}{r'^2}\\\\\dfrac{F}{F'}=\dfrac{\dfrac{kq_1q_2}{r^2}}{\dfrac{kq_1'q_2'}{r'^2}}\\\\\dfrac{F}{F'}=\dfrac{\dfrac{q_1\times q_2}{r^2}}{\dfrac{2q_1\times 3q_2}{(2r)^2}}\\\\\dfrac{F}{F'}=\dfrac{4}{6}=\dfrac{2}{3}\\\\F'=\dfrac{3\times 4.2\times 10^{-2}}{2}\\\\F'=0.063\ N[/tex]
So, the new force is 0.063 N.
Answer:
The force becomes 0.0315 N.
Explanation:
Force, F = 4.2 x 10^-2 N
When the distance is doubled, a charge is tripled, Let the force is F'.
The force between the two charges is
[tex]F = \frac{K qq'}{r^2}\\[/tex]
when, q' = 3 q' and r is 2 r so
[tex]F' = \frac{K 3qq'}{4r^2} = \frac{3 F}{4} = \frac {3\times 4.2\times 10^{-2}}{4}=0.0315 N[/tex]
A student initially 10.0 m East of his school walks 17.5 m West. The magnitude of the student's displacement, relative to the school is _________ m? The direction of the student's displacement, relative to the school is ______?
Answer:
1. 7.5 m
2. towards west side
explanation:
I hope it will help you
79. A skater glides along a circular path of radius 5.00 m in clockwise direction. When he coasts around one-half of the circle, starting from the west point, find (a) the magnitude of his displacement vector and (b) how far he actually skated. (c) What is the magnitude of his displacement vector when he skates all the way around the circle and comes back to the west point
The potential difference across a resistor increases by a factor of 4. How
does the current change? (Ohm's law: V = IR)
A it increases by a factor of 4
B it decreases by a factor of 4
C it increases by a factor of 2
D it decreases by a factor of 2
Answer:
Correct option is C it decreases by a factor of 2
Answer: A - it increases by a factor of 4
Explanation:
Ohm's law is V = IR where V = potential difference, I = current, and R = resistance. Assuming that resistance stays constant (since the question mentioned no change in resistance), we only need to look at "V" and "I" in the equation V = IR.
"V" and "I" are directly proportional. In other words, whatever change happens to "V" will also occur to "I". Since "V" increases by a factor of 4, then "I" will also increase by a factor of 4.
You could also approach this problem by plugging in a change of 4 for the potential difference in the equation: V = I*R.
If we plug in 4V for V, we now have:
4V = I*R
Since the left side increases by a factor of 4, then the right side (only looking at current in this case) will also need to increase by a factor of 4 in order to have the right side stay equal to the left. Therefore, current will also increase by a factor of 4.
Question 12 of 15
If nitrogen, which has an electronegativity of 2.0, bonds with hydrogen, which
has an electronegativity of 2.1, the bond between the two atoms will be
classified as a(n)
covalent bond.
Answer here
SUBMIT
Answer:
Covalent bond.
Explanation:
There are 4 main types of bonds:
Covalent, ionic, metallic, and hydrogen.
Covalent bond: Involves the sharing of pairs of electrons, here the difference between the electronegativity of the atoms is not too large. Covalent bonds usually form an octet of electrons.
Ionic bond: This happens because the electrostatic attraction between the atoms whit very different electronegativities
Hydrogen bond: Electrostatic attractive force between an electronegative atom and a hydrogen atom covalently bonded to another electronegative atom.
Metallic bond: Type of bond that makes the metallic atoms to stay really tightly together. The atoms bond because of the electrostatic atractive force between conduction electrons and positively charged metal ions.
Now, in this case, we have the bond between Nitrogen (electronegativity = 2.0) and Hydrogen (electronegativity = 2.1)
So we can see that:
The elements are not metals, so we can discard metallic bond.
For a hydrogen bond, we need 3 atoms (one of which is hydrogen), here we have two, so we can discard this option.
Ionic bond needs different electronegativities, here the electronegativities are really close together, so the ionic bond can be discarded.
we can conclude that the bond will be a covalent bond.
True or false: Ultimate tensile strength increases as the thickness of a solid material sample increases.
True
False
Answer:
False.
Explanation:
Tensile strength should remain constant, regardless of thickness. For larger cross sections, it can slightly increase because the atoms in the center become more constricted and therefore less responsive to the applied stress.
Answer:
Tensile strength should remain constant, regardless of thickness. For larger cross sections, it can slightly increase because the atoms in the center become more constricted and therefore less responsive to the applied stress.FALSE
