Answer:
When the water is frozen it turns to ice and the density decreases.
Explanation:
Have A Wonderful Day !!
A box weighs 1300 N. When a horizontal force of 390 N has applied the box accelerates at 1.3 m/s2. What is the magnitude of the frictional force?
Answer:
Ffriction = 217.7[N]
Explanation:
First, we must find the mass of the box, we must remember that the weight is defined as the product of the mass by acceleration.
[tex]w=m*g[/tex]
where:
w = weight [N] (units of Newtons)
m = mass [kg]
g = gravity acceleration = 9.81 [m/s²]
[tex]1300=m*9.81\\m=132.51[kg][/tex]
Now we must use Newton's second law, which tells us that the sum of forces is equal to the product of mass by acceleration.
∑F = m*a
where:
∑F sum of forces
m = mass = 132.51[kg]
a = acceleration = 1.3[m/s²]
We must know that the forces that act are the horizontal force that moves the box and the friction force in the negative direction that acts against the movement.
Now replacing:
[tex]390-f_{friction}=132.51*1.3\\390-172.26=f_{friction}\\f_{friction}=217.7[N][/tex]
A car battery produces 12 from electric that each produce 2.0 V. What is the minimum number of electric cells in car battery?
Answer:
6
Explanation:
From the given question, since a total of 12 V was obtained from the battery which is made up of a number of cells with each producing 2.0 V.
Assuming that the cells have a very low internal resistance, then;
minimum number of electric cells in the car battery = [tex]\frac{total voltage from the cells}{individual voltage of the cells}[/tex]
= [tex]\frac{12}{2}[/tex]
= 6
Thus, the minimum number of electric cells in the car battery is 6.
This implies that the addition of 6 cells which has 2.0 V supply in the battery produces a total of 12 V. Provided that the cells have a very low internal resistance.
velocity of sound in solid is more than that in liquid.why?
Velocity of sound travels faster in solids than in liquids, and faster in liquids than in gases because "the density of solids is higher than that of liquids, meaning that the particles are closer together."
Answer:
Explanation:
Due to the fact that sound is caused by vibrations, it's more noticeable in liquid because the vibrations may cause ripples in the liquid
A student pulls a block across the desk in physics class. He applies 14N of
tension in the string, but friction holds the box back with 4N. His partner
measures the acceleration of the box across the desk to be 2m/s2. What
must the mass of the box be?
100 Pointsss hellppp
can you please show a picture
aluminum has a density of 270 kg/m3. what volume of aluminum would have a mass of 49.9 kg?
(unit = m^3)
0.184[tex]m^{3}[/tex] is the answer for Acellus students!
An object is subject to a 84 Nm torque about a point when a
21 N of force is applied to a second point along the object's
length. How far apart are the two points
Answer:
d = 4[m]
Explanation:
Torque in physics is defined as the product of force by distance. This way you can use the following equation to calculate the torque.
[tex]T=F*d[/tex]
where:
T = torque [N*m]
F = force [N]
d = distance [m]
Now replacing in the equation above.
[tex]84=21*d\\\\d= 4[m][/tex]
Find the work done by a man who is pulling a box of 45kg of mass by means of rope which makes angle of 45 degrees.
Answer:
0
Explanation:
Since no distance is given, the force is not doing any work
No work is done by the man since we do not know the distance or displacement.
Work is only said to be done when the force applied on an object moves it through a particular distance.
Work done = Force x distance.
Since no distance is given in this problem, we can as well assume that the force applied is doing no work on the object.
What is the gravitational force of attraction between a 55 kg boy and a 40 kg girl if they are 0.10 meters apart?
Answer:
[tex]1.5\cdot 10^{-5}\:\mathrm{N}[/tex]
Explanation:
Newton's Law of Gravitation is given as:
[tex]F=G\frac{m_1m_2}{r^2}[/tex], where [tex]G[/tex] is gravitational constant [tex]6.67\cdot 10^{-11}[/tex] and [tex]r[/tex] is the distance between their centers of mass.
Therefore, the gravitational force between them is:
[tex]F=6.67\cdot 10^{-11}\frac{55\cdot40}{0.1^2}= \fbox{$1.5\cdot 10^{-5}\:\mathrm{N}$}[/tex] (two significant figures).
A ‘can-chiller’ is used to make a can of drink colder. The initial temperature of the liquid in the can was 25.0 °C. The can-chiller decreased the temperature of the liquid to 20.0 °C. The amount of energy transferred from the liquid was 6930 J. The mass of liquid in the can was 0.330 kg.
Calculate the specific heat capacity of the liquid. Give the unit.
Please help :)
Answer:
4200 J/°C/kg
Explanation:
The formula for heat transfer is given by :
Q= m*c*ΔT where;
Q= heat transferred = 6930 J
m=mass of the liquid = 0.330 kg
c= specific heat capacity=?
ΔT = 25-20 = 5.0°C
Applying the values in the formula as;
Q= m*c*ΔT
6930 = 0.330 * c * 5
6930 = 1.65 c
6930/1.65 = c
4200 = c
c= 4200 J/°C/kg
Janet jumps off a high diving platform with
a horizontal velocity of 2.6 m/s and lands in
the water 1.5 s later.
How far from the base of the platform
does she land? The acceleration of gravity
is 9.8 m/s?
Answer in units of m.
Answer:
11.025m
Explanation:
In this question there is no vertical velocity,
t= 1.5s
Height of platform=h
From Newton equation
s = ut + 1/2gt^2
But there is no vertical velocity,
Hence,
Then u=0
h = 0 + 1/2 x 9.8 x (1.5)^2
h = 11.025m
What type of wave did you create when you pushed your arm back and forth?
plz help
Answer: It is a transverse wave ^^
Explanation:
An object moving at a constant velocity accelerates at a constant rate of 2.5 m/s2 for a distance of 30 m. At the end of the acceleration the object has a velocity of 90 m/s. What was its velocity before accelerating?
Answer:
The initial velocity is 89.16m/s
Attached is the solution
Explanation:
Henry designs an experiment to find out why plants without flowers tend to be wind-pollinated and not animal-pollinated. He takes samples from a variety of plants and studies them in the field. He finds that the evidence supports his hypothesis. Which of these was the hypothesis Henry was testing? Choose the correct answer. Nonflowering plants make less pollen than flowering plants. Nonflowering plants lack the structures to attract animal pollinators. Nonflowering plants grow close to the ground and capture fewer pollinators. Nonflowering plants grow close to the ground because they have no pollen grains.
Answer:
option 2
Explanation:
you are very welcom
The Periodic Table Question 3 of 10 Based on the trend in valence electrons across periods for main-group elements, how many valence electrons does fluorine (F) have? O A. 4 B. 7 O C. 6 D. 5 SUBT
Answer:
B. 7
Explanation:
Fluorine has 7 valence electrons in its orbitals.
The valence electrons are electrons in the outermost shell of an atom. Every element has a certain amount of valence electrons.
Fluorine belongs to the 7 - group on the periodic table. Every element in this group has 7 electrons in their outermost shell. The elements in the group are called halogens. Other elements in this group are fluorine, chlorine, bromine, iodine and astatine.Answer:
7
Explanation:
A horizontal pole is attached to the side of a building. There is a pivot P at the wall and a chain is connected from the end of the pole to a point higher up the wall. There is a tension force F in the chain. What is the moment of the force F about the pivot P?
Answer:
Fscos63
Explanation:
Given that a horizontal pole is attached to the side of a building. There is a pivot P at the wall and a chain is connected from the end of the pole to a point higher up the wall. There is a tension force F in the chain. What is the moment of the force F about the pivot P?
Taking the moment from the pivot point P, that means the moment at point p = 0
Then, if we consider the weight mg of the pole, according to the principle of equilibrium : sum of the upward forces equal to the sum of the downward forces.
Therefore, mg = Fsinø ....... (1)
Also, taking moment at point P
Let the length of the pole = s
The length of the weight of the pole = 1/2 S
Fscosø = mgs/2
The distance s will cancel out
2Fcosø = mg ...... (3)
Substitute mg in equation 1 into equation 3
2fcosø = fsinø
F will cancel out
Tanø = 2
Ø = tan^-1(2)
Ø = 63.4 degree
The moment of force F about pivot point P will be
Moment = force × distance
Moment = Fcos63 × S
Moment = Fscos63
A 2-kg ball traveling eastward at 5 m/s hits a 5-kg ball moving at 1 m/s eastward. The 2-kg ball bounces west at 3.0 m/s. What is the speed of the 5kg ball?
Answer:
1.8 m/s
Explanation:
Step one:
given data
m1= 2kg
u1= 5m/s
m2= 5kg
u2= 1m/s
v1= 3m/s
From
m1u1+m2u2= m1v1+m2v2
substitute
2*5+5*1 = 2*3+5*v2
10+5= 6+5v2
15-6= 5v2
9= 5v2
divide both side by 5
v2= 9/5
v2= 1.8 m/s
Hi!! Does anyone know this answer? :D
Answer:
Im not fully corrrect but I would say C
Explanation:
A 10.0kg box sits at rest on ramp that has an incline of 20.0° from the horizontal. What is the force of gravity acting on the box?
A. -98.0N
B. 98.0N
C. -92.1N
D. -33.5N
Answer:
98.0N
Explanation:
A body with mass 2 kg absorbs heat 418.4J when its temperature raises from 293K to 343K . What is the specific heat of the body?
Answer:
C M (change in T) = heat absorbed thermal equation for heat gained
C = 418.4 J / (2 kg * 50 deg K) = 4.184 J / kg * deg K specific heat
Note: 1 gm =.001 kg
So C = .004184J / gm * deg K
Also, 1 J = .239 cal so in conventional terms
C = .001 cal / gm deg K (very low, water would be 1 cal / gm deg C
Which idea did Ptolemy's model use to explain why the planets appeared to move backward as they moved in their orbits? The planets spun in epicycles. The planets rotated on their axes. The planets revolved around the Sun. The planets were made of different materials.
Answer:
The planets spun in epicycles.
Explanation:
The planets were not simply attached to a mystical sphere (“deferent”) but they were actually attached to a mini-sphere (“epicycle”) which rotated on the larger one.
Answer:A
Explanation:
a) Las siglas M. RU significan
Answer:
Ver la explicación a continuación.
Explanation:
En física estas siglas significan movimiento rectilíneo uniforme, es decir es el tipo de movimiento donde la velocidad es constante. La velocidad no cambia con el tiempo.
Este tipo de movimiento se puede describir con la siguiente ecuación.
[tex]x=x_{0}+v*t[/tex]
Donde:
x = posición final [m]
xo = posición inicial [m]
v = velocidad [m/s]
t = tiempo [s]
Please help me this is worth allot
1) Which of the following is not a type of energy?
A: Thermal
B: Potential
C: Kinetic
D: Frictional
From what Tim explains in the movie, what can you infer about the temperature inside a refrigerator?
Answer:
It's closest to 3 degrees celsius
Explanation:
What is the same about a particle as gas, liquid, or solid?
A. The speed at which the particles move.
B. The volume that the substance takes up.
C. The chemical composition.
D. The temperature of the substance.
The thing same about a particle as gas, liquid, or solid is its chemical composition.
What are states of matter?
Matter exists in three different states: solid, liquid, and gas. By examining the configuration of their particles, it is possible to understand why they have various qualities. Theoretically, at this temperature, particles move slowly and have the least amount of energy.
Phase refers to the material's actual state. To pay attention to is the word physical. Only physical means can change the state of matter. You can make a physical change if energy is added (by raising the temperature) or subtracted (by freezing things).
The chemical composition of matter same about a particle as gas, liquid or solid.
To learn more about states of matter refer to the link:
brainly.com/question/9402776
#SPJ5
A person runs 15.0 km north then turns around and runs 10.0 Km south. what is his dstance
Answer:
25km
Explanation:
The person runs 15km Northward
Turns around and runs 10km southward
The distance is the length of path covered by the person running.
This is given as:
Distance = Distance North + Distance South
Distance = 15km + 10km = 25km
Answer:
25km
Explanation:
cant explain but ik
If Minnie the Mouse starts moving at 2m/s and increases her velocity to 4m/s because she is being chased, what is heracceleration if the time is 2 seconds?
Answer:
1m/s²
Explanation:
Given parameters:
Initial velocity = 2m/s
Final velocity = 4m/s
Time of chase = 2s
Unknown:
Acceleration = ?
Solution:
Acceleration is the rate of change of velocity with time;
A = [tex]\frac{v - u }{t}[/tex]
A is the acceleration
v is the final velocity
u is the initial velocity
t is the time taken
A = [tex]\frac{4 - 2}{2}[/tex] = 1m/s²
In a normal Earth atmosphere, a feather will free fall through the air more slowly than a brick because of what force?
A. Terminal velocity
B. Momentum
C. Weightlessness
D. Air Resistance
Answer:
Air Resistance
Explanation:
Because air gives a much greater resistance to the falling motion of the feather than it does to the brick.
Which of these pairs of atoms are isotpoes? (Physical Science) Pair A Pair B Pair C # protons 6 8 5 2 12 12 # neutrons 8 8 5 3 13 14
Answer:
I guess that the atoms are:
Protons: 6 8 5 2 12 12
Neutrons: 8 8 5 3 13 14
Now, two atoms are isotopes if they share the same number of protons (so both atoms are the same element) but they have a different number of neutrons.
From the given options, the only two that have the same number of protons but a different number of neutrons are:
Protons 12, neutrons 13
and
Protons 12, neutrons 14.
These two are isiotopes.
Select ALL of the places you might find DNA evidence.
saliva on gum
blood spatter on the wall
inside a femur bone found in the woods
cells on root of hair found at the scene
Answer:
Inside a femur bone found in the woods,
saliva of gum
