Answer:
0.7432m²
1152in²
Explanation:
a) Usng the conversion
1ft² = 0.0929m²
8ft² = y
y = 8 × 0.0929
y = 0.7432m²
Hence 8ft² in m² is 0.7432m²
For ft² to in²
1ft² = 144in²
8ft² = x
X =8×144
x = 1152in²
Hence 8ft² expressed in in² is 1152in²
How come the arrow points the other direction when we look at it through a glass of water?
A truck is carrying a load of furniture and has a momentum of 33,842 kg m/s. If half of the furniture falls off the truck (mass is cut in half), what is the truck’s new momentum?
Answer:
16921
Explanation:
Usually, if and when the truck does lose part of its load, or load gets cut into half, then it's momentum gets reduced to half of the original momentum. This is because, from the definition of momentum, we understand that it's the multiplication of mass and velocity. This means that if the mass gets reduced to half, then the total momentum goes ahead to be reduced to half just as well.
New momentum = 1/2 * 33842
New momentum = 16,921 kg∙m/s.
A pilot must fly his plane due north to reach his destination. The plane can fly at 300 km/h in still air. A wind is blowing out of the northeast at 90 km/h. (a) What is the speed of the plane relative to the ground
Answer:
229.5 km/h
Explanation:
Given that
Velocity of the plane relative to the ground = V.pg = ?
Velocity of air relative to the ground = V.ag = 90 km/h
Velocity of the plane relative to air = V.pa = 300 km/h
V.pg = V.ag + V.pa
Where
V.ag = 90 km/h
= -90 cos 45i - 90 sin 45j
V.pa = 300 km/h
= 300 cos θi + 300 sin θj
V.pg = [-90 cos 45i - 90 sin 45j] + [300 cos θi + 300 sin θj], on rearranging and collecting like terms
V.pg = [300 cos θ - 90 cos 45]i + [300 sin θ - 90 sin 45]j
If vector i = 0, then
300 cos θ - 90 cos 45 = 0
300 cos θ = 90 cos 45
cos θ = 90 cos 45 / 300
cos θ = 63.6396 / 300
cos θ = 0.2121
θ = cos^-1 0.2121
θ = 77.75
We then use this θ to find vector j
V.pg = 300 sin θ - 90 sin 45
V.pg = 300 sin77.75 - 90 sin45
V.pg = 293.1693 - 63.6396
V.pg = 229.5297 km/h
An object accelerates downward at a constant rate of 2.00 m/s2 while completely submerged in water. Neglect the viscosity (fluid friction) of the water. The average density of the object is ______ kg/m3. Use g
Answer:
833kg/m³
Explanation:
We have volume as Vm³
Density of this object = dKg/m³
Water density = 1000kg/m³
g = 10m/s²
We calculate FB which is the the buoyant force on object. Calculated as volume of object multiplied by water density
Fb = 1000Vg upwards
W = Vdg
Acceleration = net upwards/m
M = mass
2 = (1000g-gd)/d
2d = 10000 - 10d
2d + 10d = 10000
12d = 10000
d = 833.33kg/m³
Approximately 833kg/m³
The average density of the object is therefore 833kg/m³
A force of 25 N acts on a 4.75 kg object for 8.4 s. What is the object's change in momentum?
Calculate the average (mean) of these numbers: 6, 5, 7, 9.8*
1. 35
2. 8.75
3. 5
4. 7
Answer:
13.94 to 2 d.p
Explanation:
just add them all up and i am confused the ones you said or the ones listed ?
the one i did was the listed ones
Helppp plssss I am needing help for science and there is a photo pls answer
Answer:
sorry I don't really know :P
Explanation:
Answer:
how many of those questions do you need answers to?
Explanation:
If an ice cube has a mass of 5g and is left in the sun in a beaker, what will happen to its mass?
Answer:
The mass remains the same
Explanation:
An ice cube of mass 5g left in the sun in a beaker will have no mass difference.
For this system, mass is conserved.
The ice cube begins to melt and the state changes. The state change is from solid to liquid. Since no mass is loss, the mass of the liquid formed and the ice will remain the same. In retrospect, this physical change ensures that mass is conserved.A record rotates on a turntable at 33 rpm. You may want to review What is the angular speed in rad/s?
Answer:
the angular speed in rad/s is 3.45
Explanation:
The computation of the angular speed in rad/s is as follows:
As we know that
1 rpm means 1 revolution per minute
Also 1 minute = 60 seconds
SO, for 33 rpm, the angular speed is
= 33 ÷ 60 × 2π
= 3.45 rad/s
As the revolution is of 360 degrees i.e. equivalent to 2π
Hence, the angular speed in rad/s is 3.45
Suppose a race car accelerates horizontally 7.6 m/sec2 for 5.5 seconds. Assume the initial
velocity of the car is zero. How far did the race car travel while accelerating? This is a
displacement calculation.
Give your answer in standard form.
Answer:
d = 114.95 m
Explanation:
Givens:
a = 7.6 m/s^2
t = 5.5 s
v_i = 0 m/s
a = (v_f-v_i)/t
7.6 m/s^2 = (v_f-0 m/s)/5.5 s
v_f = (7.6 m/s^2)*(5.5 s)
v_f = 41.8 m/s
d = [(v_f+v_i)/2]*t
d = [(41.8 m/s)/2]*5.5 s
d = 114.95 m
A 3.00-g bullet has a muzzle velocity of 230 m/s when fired by a rifle with a weight of 25.0 N. (a) Determine the recoil speed of the rifle. 0.27 Correct: Your answer is correct. m/s (b) If a marksman with a weight of 650 N holds the rifle firmly against his shoulder, determine the recoil speed of the shooter and rifle. Incorrect: Your answer is incorrect.
Answer:
0.27 m/s and 0.01 m/s
Explanation:
Given that
Mass of the bullet, m = 3 g = 0.003 kg
Velocity of the bullet, v = 230 m/s
Weight of the rifle, w = 25 N
From this, we know that the mass of the rifle, M = 25/9.8 = 2.55 kg
Using the law of conservation of momentum, we know that
Momentum of the gun = momentum of the bullet
M.g * V.g = m.b * v.b
2.55 * V.g = 0.003 * 230
2.55V.g = 0.69
V.g = 0.69 / 2.55
V.g = 0.27 m/s
If weight of the shooter = 650, then his mass = 650/9.8 = 66.33 kg
The recoil speed of the shooter is
0.69 / 66.33 = 0.010 m/s
explain why astronauts around the earth either in spaceship, a space station, or on a spacewalk appear to be weightless but are not actually weightless.
Answer:
Zero gravity
Explanation:
Astronauts around the earth either in spaceship, a space station or on a space walk appear to be weightless because of the zero gravity in such environment.
Weight is a function of the mass and acceleration due to gravity a body has.
Weight = mass x acceleration due to gravity
In a place where acceleration due to gravity is 0, the weight would be zero and a person would appear to be weightless.
Which color of visible light has a higher frequency than blue light?
A. Green
B. Yellow
C. Red
D. Violet
Answer:
D. violet
Explanation:
think of a UV light
A baseball player uses a pitching machine to help him improve his batting average. He places the 67.1 kg machine on a frozen pond. The machine fires a 0.101 kg baseball horizontally at a speed of 32.6 m/s. What is the magnitude of the recoil velocity of the machine
Answer:
The magnitude of the recoil velocity of the machine is 0.05 m/s.
Explanation:
Given;
mass of the baseball, m₁ = 0.101 kg
mass of the machine, m₂ = 67.1 kg
velocity of the baseball, v₁ = 32.6 m/s
let v₂ be the recoil velocity of the machine.
Apply the principle of conservation of linear momentum; the total momentum before and after firing the ball must be constant.
sum of the initial momentum of the ball and the machine = 0 (at rest)
sum of the final momentum of the ball and the machine = m₁v₁ + m₂v₂
Since total momentum is constant; m₁v₁ + m₂v₂ = 0
m₁v₁ + m₂v₂ = 0
(0.101 x 32.6) + (67.1)v₂ = 0
67.1v₂ = -3.2926
v₂ = (-3.2926) / 67.1
v₂ = -0.05 m/s (the negative sign shows that it is the opposite direction)
Thus, the magnitude of the recoil velocity of the machine is 0.05 m/s.
The force f is given in terms of time t and displacement X by the equation F= Asin Bx +C sin dt. What is the dimension of D/B?
Answer:
Here's what I think,
A_Trigonometric_ratio (whatever)
The general form of sin/cos/tan(angle).
So here as in the general form the "whatever" is always an "angle" input which (may sound a bit unfair but) is a dimensionless quantity.
As mentioned in your question,
F= Asin(Bt) + C cos (Dy)
Dimentions of these terms will be same (by homogenity of dimensions).
So what we gotta do here is make Bt and Dy dimensionless for this whole equation to work.
According to your question t is time,
So to make Bt dimensionless,
B must be equal to inverse of time i.e T^(-1)
Using the same process on Dy, gives inverse of length i.e L^(-1)
So,
B= M^(0)L^(0)T^(-1)
D = M^(0)L^(-1)T^(0)
The dimension of D/B then will be M^(0)L^(-1)T^(1)
What is the internal resistance of a 12.0 V car battery whose terminal voltage drops to 8.2 V when the starter draws 75 A
Answer:
The internal resistance of the cell is 0.051 ohm.
Explanation:
Given;
emf of the battery, E = 12 V
terminal voltage of the cell, V = 8.2 V
current in the circuit, I = 75 A
let the potential drop of the cell due to internal resistance (r) = Ir
The internal resistance of the cell is calculated from the equation below;
E = V + Ir
where;
r is the internal resistance of the cell
[tex]Ir = E - V\\\\r = \frac{E-V}{I} \\\\r = \frac{12-8.2}{75} \\\\r = 0.051 \ ohm[/tex]
Therefore, the internal resistance of the cell is 0.051 ohm.
The % DV (percent Daily Value) is based on an average 2,000-calorie diet. One gram of carbohydrate provides 4 calories of energy. If Anna’s doctor recommends getting 60% of her calories from carbohydrates, how many grams of carbohydrates should she consume each day?
Answer:
300
Explanation:
If the %DV is based on an average 2,000 calorie diet, and one gram of carbohydrate provides 4 calories, you would divide 2,000 by 4.
2,000 divided by 4 equals 500.
If Anna's doctor recommends 60% of her calories, you find out how much 60% of 500 is.
60% of 500 is 300.
Anna should consume 300 grams of carbohydrates daily.
Hope this helps!
Answer:
300
Explanation:
A baseball has an approximate mass of 0.15 kg. If a bat strikes the baseball with a force of 6 N, what is the acceleration of the ball?
Answer:
a = 40 [m/s²]
Explanation:
These kinds of problems can be solved using Newton's second law, which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
∑F = m*a
where:
F = force = 6 [N]
m = mass = 0.15 [kg]
a = acceleration [m/s²]
[tex]a=F/m\\a=6/0.15\\a=40[m/s^{2} ][/tex]
Answer:
40 .............vxfhgcffffxxxhhxcjcxghxfgxsfg
A bungee cord stretches 25 meters and has a spring constant of 140 N/m. How much energy is stored in the bungee cord
Answer:
The energy stored in the bungee cord is 43,750 J.
Explanation:
Given;
extension of the bungee cord, x = 25 m
spring constant of the bungee cord, k = 140 N/m
The elastic potential energy stored in the bungee cord is calculated as;
U = ¹/₂kx²
U = ¹/₂(140)(25)²
U = 43,750 J
Therefore, the energy stored in the bungee cord is 43,750 J.
Predict Phenomena A positively charged particle is placed next to an
negatively charged object. In which direction does the positively charged
particle move? Explain why.
Answer:
The positively charged particle will move towards the negatively charged particle.
Explanation:
According to Coulomb's Law, there are two types of charges--positive charge and negative charge. Coulomb said that they are either attractive or repulsive but the basic law in charges states that opposite attracts. Since they (the two charged objects) are oppositely charged, they will then move towards one another.
A plastic ball has mass M. It floats in water with (1/5)th of its volume under the water line. What downward force must be applied to the ball to submerge it and hold it at rest below the surface of the water
Answer:
F = -4/5 W
Explanation:
We will do this exercise in parts, let's start with the data, The ball must be in balance
B -W = 0
B = mg (1)
where the thrust is given by Archimedes' principle
B = ρ g V_liquid
In the problem we are told that the volume of the submerged body is 1/5 of the volume of the body, let's use the subscript 2 for the ball and the subscript 1 for the liquid
V₁ = [tex]\frac{1}{5}[/tex] V₂
if we use the concept of density for the body
ρ₂ = m / V₂
m = ρ₂ V₂
We can see that mass and volume are directly proportional, so we can use a rule of three to find the submerged mass. If mass M is in volume V₂ what mass is there in volume V₂ /5
m₂ = [tex]\frac{V_{2} }{5} \frac{M}{V_{2} }[/tex]
m₂ = M / 5
we substitute in equation 1
B = M / 5 g
This is the thrust that is an upward vertical force, therefore to submerge the whole ball we must apply a downward vertical force equal to the rest of the weight, the equilibrium condition in this case is
B -W - F = 0
F = B -W
F = [tex]\frac{M}{5}[/tex] g - M g
F = -4/5 Mg
F = -4/5 W
The negative sign indicates that the force is vertical down
When Mary talks, she creates an intensity level of 60 dB at your location. Alice talks with the same volume, also giving 60 dB at your location. If both Mary and Alice talk simultaneously from the same spot, what would be the new intensity level that you hear
Answer:
hm
Explanation:
facil
single phase ac voltage of 240 v is applied to a series circuit whose impedance is 10 60 find the resistance
Complete question
Single phase ac voltage of 240 v is applied to a series circuit whose impedance is 10<60 find the resistance
Answer:
[tex]R=5 ohms[/tex]
Explanation:
From the question we are told that
Voltage[tex]V=240[/tex]
Impedance[tex]Z= 10<60[/tex]
General converting from polar to Cartesian form is given by
[tex]X=r*cos \theta[/tex]
[tex]Y = r * sin\theta[/tex]
Therefore
[tex]X=10 cos 60\texdegree[/tex]
[tex]X=5[/tex]
[tex]Y = 10 sin 60\textdegree[/tex]
[tex]Y = 8.660[/tex]
Therefore
[tex]Z=5+j8.660[/tex]
Generally the equation impedance is mathematically given as
[tex]Z=R+jX[/tex]
where
R is Resistance
X is Reactance
Therefore
[tex]R=5 ohms[/tex]
A tourist drops (from rest) a ping pong ball from the top of the tower, which has a height of 324 meters. Assuming no air resistance, how long does it
Answer:
8.13secs
Explanation:
From the question weal are given
Height H =324m
Required
time it takes to drop t
Using the equation of motion
H = ut + 1/2gt²
Substitute the given values
324 = 0(t)+1/2(9.8)t²
324 = 1/2(9.8)t²
324 = 4.9t²
t² =324/4.9
t² = 66.12
t = √66.12
t = 8.13secs
Hence the time taken to drop is 8.13secs
What is the maximum force that the student could apply to a 220kg object on the same surface before the box would start to slide
Answer:
Force needed to move the box is 2,158.2N
Explanation:
Step one:
We are given that the mass =220kg
The force needed to overcome friction is the same as the weight of the box
Step two :
So from
F=mg
W=mg
Substitute
W=220*9.81
W=2,158.2 N
if you go to space at 15000 mph. how long would it take you at the same speed to reach mars
Answer:
if your going 15000 mph all you can do is accelerate or go fast unless there is a opposite
Explanation:
what does it mean to say that mass is conserved during a physical change?
Answer:
Explanation:
When a physical change occurs, the mass of the substance is conserved. This means that the total mass of the substance remains the same from beginning to end. The physical properties of the substance, such as size and shape, may change, but the amount of matter in the substance does not change.
( sample response )
what is one reason that john adams and benjamin franklin believed the articles of confederation should be revised.
Answer:
Explanation:
Their most intimate experience probably happened during an unsuccessful peace mission in September 1776. The British forces had recently raced across Long Island (New York) and almost destroyed the American Army. The British commander, Adm. Lord Richard Howe, then offered peace. Congress sent Adams, Franklin, and Edward Rutledge (South Carolina) to meet Howe on Staten Island.
Howe hoped to resolve the differences between what Great Britain still considered its colonies and the mother country. The Americans insisted on British recognition of independence, but Howe had no such authority, and Adams and Franklin had little of their own. Although cordial, the meeting broke up without success after just three hours.
During the mission, Adams and Franklin lodged together at crowded inn in a small room with only one window. Adams records an unforgettable and amusing story in his diary about that evening and hearing Franklin’s theory of colds.
A system dissipates 12 JJ of heat into the surroundings; meanwhile, 28 JJ of work is done on the system. What is the change of the internal energy ΔEthΔEthDeltaE_th of the system?
Given that,
A system dissipates 12 J of heat into the surroundings.
28 J of work is done on the system.
To find,
The internal energy of the system.
Solution,
The first law of thermodynamics is used here. According to this law,
[tex]\Delta E=Q-W[/tex]
Q is heat and W is work done
Here,
Q = -12 J is the heat dissipated by the system
W = -28 J is the work done on the system
ATQ,
[tex]\Delta E=(-12)-(-28)\\\\=-12+28\\\\=16\ J[/tex]
So, the change of internal energy of the system is 16 J.
What type(s) of charges will be free to move around independently in a conductor under typical classroom conditions
Answer:
it is electron that is free to move in conductor