Answer:
Ro = 8.65 [g/cm³]
Explanation:
We must remember that density is defined as the ratio of mass to volume.
[tex]Ro=m/V[/tex]
where:
m = mass = 0.450 [kg] = 450 [g]
V = volumen = 52 [cm³]
Ro = density [g/cm³]
Now replacing:
[tex]Ro = 450/52\\Ro = 8.65 [g/cm^{3} ][/tex]
What average net force is required to stop a 3.5 kg bowling ball initially travelling at a speed of 1.5 m/s over a distance of 0.4 m?
First the aceleration:
Vf² = Vo² - 2ad
a = (Vf² - Vo²) / 2d
a = (0 m/s)² - (1,5 m/s)²) / 2 * 0,4 m
a = -2,25 m²/s² / 0,8 m
a = -2,81 m/s²
Now, for the net force, use 2nd law of Newton:
F = ma
F = 3,5 kg * (-2,81 m/s²)
F = -9,835 N
The force for stop the bowling ball is -9,835 Newtons.
4. What is the tan gential velocity of an object moving in a path of radius 2m with an angular velocity of
3rad/s.pls help me
Answer:
6m/s
Explanation:
The tangential velocity is the product of the linear velocity and the radius. This is expressed as;
v = wr
w is the angular velocity = 3rad/s
r is the radius = 2m
Substitute
v = 3 * 2
v = 6m/s
Hence the tangential velocity of the object is 6m/s
A submarine window has 1730 N of
force on it, due to water pressing it
with 2.45 atm of pressure. What is
the area of the window?
(Unit = m^2)
As always, keep 3 sig figs.
Enter
Answer:
0.007
Explanation:
A = F/P
Force = 1730
P = 2.45 = 2.47 * 10^5
1730/(2.47*10^5) = 0.007
Answer:
Hi.
The answer to this problem is 0.007
Explanation:
It was correct for Acellus
How to solve it:
P=F/A
Rearrange it for A, plug in the numbers and solve!
A=F/P
F=1,730
P=2.45
A local FM radio station broadcasts at a frequency of 97.3 MHz. Calculate the energy of the frequency at which they are broadcasting. Energy
Answer:
6.45×10¯²⁶ J
Explanation:
From the question given above, the following data were obtained:
Frequency (f) = 97.3 MHz
Energy (E) =?
Next, we shall convert 97.3 MHz to Hz. This can be obtained as follow:
1 MHz = 1×10⁶ Hz
Therefore,
97.3 MHz = 97.3 MHz × 1×10⁶ Hz / 1 MHz
97.3 MHz = 9.73×10⁷ Hz
Thus, 97.3 MHz is equivalent to 9.73×10⁷ Hz.
Finally, we shall determine the energy at which the frequency is broadcasting. This can be obtained as follow:
Frequency (f) = 9.73×10⁷ Hz
Planck's constant (h) = 6.63×10¯³⁴ Js
Energy (E) =?
E = hf
E = 6.63×10¯³⁴ × 9.73×10⁷
E = 6.45×10¯²⁶ J
Therefore, the energy at which the frequency is broadcasting is 6.45×10¯²⁶ J
A constant net force of 345 N is applied to slide a heavy stationary
couch across the floor. If the force is contact with the couch for 1.5 seconds,
then what is the change in momentum of the couch
Answer:
P = 517.5 [kg*m/s]
Explanation:
We must remember that momentum is defined as the product of force by the time of force duration.
[tex]P=F*t[/tex]
where:
P = momentum [kg*m/s]
F = force [N]
t = time [s]
[tex]P=345*1.5\\P=517.5[kg*m/s][/tex]
An 85 kg man stands in a very strong wind moving at 15 m/s at torso height. As you know, he will need to lean in to the wind, and we can model the situation to see why. Assume that the man has a mass of 85 kg, with a center of gravity 1.0 m above the ground. The action of the wind on his torso, which we approximate as a cylinder 50 cm wide and 90 cm long centered 1.2 m above the ground, produces a force that tries to tip him over backward. To keep from falling over, he must lean forward.
Required:
a. What is the magnitude of the torque provided by the wind force? Take the pivot point at his feet. Assume that he is standing vertically.
b. At what angle to the vertical must the man lean to provide a gravitational torque that is equal to this torque due to the wind force?
Answer:
a) [tex]T= 72.9 Nm[/tex]
b) [tex]\Theta = 5 \textdegree[/tex]
Explanation:
From the question we are told that
Mass 85kg
Speed 15m/s
Center of gravity 1.0m
Cylinder 50 cm wide and 90 cm long centered 1.2 m above the ground
a)Generally equation for force is given by
[tex]F = 0.5 p A v^2[/tex]
Mathematically solving for force exacted
[tex]F = 0.5*1.2*0.9*0.5*15^2[/tex]
[tex]F= 60.75 N[/tex]
Mathematically solving for torque
Torque,
[tex]T = r * F[/tex]
[tex]T=1.2*60.75[/tex]
[tex]T= 72.9 Nm[/tex]
b)Generally in solving for [tex]\theta[/tex]
[tex]Tan\theta = Torque/(Mass * Gravity)[/tex]
[tex]Tan\theta = (72.9)/(85 * 9.8)[/tex]
[tex]\Theta = 5 \textdegree[/tex]
How far will a 10N force pull a car if the work done is 20J?
The two plates are now to be pushed together to a separation of d/2. The pushing together can be done either with the battery connected or with it disconnected. Which way would result in the greater electric field magnitude, and by what factor
Answer:
Electric field will be greater when the battery is connected by the factor of 2.
Explanation:
Solution:
I will be doing some algebraic calculations to answer this question:
As we know that,
Q = CV
and
C = [tex]\frac{AE_{0} }{d}[/tex]
So, when separation = d/2, then,
[tex]C^{'}[/tex] = [tex]\frac{AE_{0} }{d/2}[/tex] by rearranging we get
So,
[tex]C^{'}[/tex] = 2C
We further know that, Voltage will remain same if the battery is connected.
This further implies that,
Q = CV
So,
[tex]Q^{'}[/tex] = [tex]C^{'}[/tex]V
[tex]Q^{'}[/tex] = 2CV
[tex]Q^{'}[/tex] = 2Q
and we also know that,
Electric field E = [tex]\frac{Q}{AE_{0} }[/tex]
So, the new E or [tex]E^{'}[/tex] = [tex]\frac{Q^{'} }{AE_{0} }[/tex]
Hence,
[tex]E^{'}[/tex] = [tex]\frac{2Q}{AE_{0} }[/tex] = 2E
[tex]E^{'}[/tex] = 2E
when battery is disconnected, Q remain the same.
So,
When disconnected
E = E
E = [tex]\frac{Q}{AE_{0} }[/tex] = Same
Hence, we can see that the magnitude of the electric does not depend upon the distance of separation. Instead it does depend upon the magnitude of charge.
So, when battery is disconnected, Q is same, so the Electric field.
But when it is connected, [tex]Q^{'}[/tex] = 2Q and the [tex]E^{'}[/tex] = 2E
So,
[tex]\frac{E connected}{E disconnected} = \frac{E^{'} }{E}[/tex] = [tex]\frac{2E}{E}[/tex] = 2
Electric field will be greater when the battery is connected by the factor of 2.
Help! Help!
Alcohol abuse has...
A. only physiological aspects.
B. only psychological aspects.
C. physiological and psychological aspects.
Answer
I feel the answer is C because it could cause mental and physical trauma
Explanation:
A man weighs himself twice in an elevator. When the elevator is at rest, he weighs 824 N; when the elevator starts moving upward, he weighs 932 N. Most nearly how fast is the elevator accelerating, assuming constant acceleration?
a. 0.64 m/s
b. 1.1 m/s^2
c. 1.3 m/s
d. 9.8 m/s^2
Answer: c. 1.3 m/s^2
Explanation:
When he is at rest, is weight can be calculated as:
W = g*m
where:
m = mass of the man
g = gravitational acceleration = 9.8m/s^2
We know that at rest his weight is W = 824N, then we have:
824N = m*9.8m/s^2
824N/(9.8m/s^2) = m = 84.1 kg
Now, when the elevators moves up with an acceleration a, the acceleration that the man inside fells down is g + a.
Then the new weight is calculated as:
W = m*(g + a)
and we know that in this case:
W = 932N
g = 9.8m/s^2
m = 84.1 kg
Then we can find the value of a if we solve:
932N = 84.1kg*(9.8m/s^2 + a)
932N/84.1kg = 11.1 m/s^2 = 9.8m/s^2 + a
11.1 m/s^2 - 9.8m/s^2 = a = 1.3 m/s^2
The correct option is C
diffrence between:- movable pulley and fixed pully
Answer:
fixed pulley: A pulley system in which the pulley is attached to a fixed point and the rope is attached to the object. ... movable pulley: A pulley system in which the pulley is attached to the object; one end of the rope is attached to a fixed point and the other end of the rope is free.
Explanation:
4) Which of the following is NOT true about lysozyme:
A) it destroys bacteria
B) it cleanses and protects the eye
C) it is an enzyme
D) it is found in tears
E) it stimulates the rods and cones
EX 6-1 A ball is twirled on a 0.870 - m-long string with a constant speed of 3.36 m / s . Calculate the acceleration of the ball. Be sure to specify the direction of the acceleration.
Answer:
[tex]a=12.97\ m/s^2[/tex]
Explanation:
Given that,
The length of a string, l = 0.87 m
Speed of the ball, v = 3.36 m/s
We need to find the acceleration of the ball. The acceleration acting on the ball is centripetal acceleration. It is given by :
[tex]a=\dfrac{v^2}{r}\\\\a=\dfrac{(3.36)^2}{0.87}\\\\=12.97\ m/s^2[/tex]
So, the acceleration of the ball is [tex]12.97\ m/s^2[/tex].
What do C-microwaves reveal to scientists?
Answer:
Different wavelengths of microwaves (grouped into "sub-bands") provide different information to scientists. Medium-length (C-band) microwaves penetrate through clouds, dust, smoke, snow, and rain to reveal the Earth's surface.
the force of an electric field is proportional to to electric charge? True or False
Answer:True
Explanation:
Answer:
I am going to say true not too sure
A boy walked 4m east then 3m south find the displacement
Answer:
5m
Explanation:
[tex]4^{2}+3^{2}=5^{2}\\5^{2}=25[/tex]
Use the Pythagorean theorem to calculate the long edge of the triangle, which would be his displacement.
A 2kg object is tied to the end of a cord and whirled in a horizontal circle of radius 2 m. If the body makes three complete revolutions every second,
what is its linear speed?
And what is its centripetal acceleration?
Answer:
a) 37.70 m/s
b)710.6 m/s²
Explanation:
Given that ;
Mass of object = 2 kg
Radius of the motion = 2m
Frequency of motion = 3 rev/s
The formula to apply is;
v= 2πrf where v is linear speed
v = 2×π×2×3 =12π = 37.70 m/s
Centripetal acceleration is given as;
a= 4×π²×r×f²
a= 4×π²×2×3²
a=710.6 m/s²
Identify the velocity-versus-time plot(s) that correspond to motion under a constant, non-zero acceleration.
Answer:
See explanation
Explanation:
The question is incomplete because the images were not attached but I will try to help you as much as possible.
Constant acceleration implies that the velocity increases uniformly with time.
The graph of constant acceleration is a straight line graph having a slope. The slope of the graph is constant at any point along the straight line.
The image attached shows a velocity-time graph depicting constant acceleration.
A bicycle has a momentum of 36 kg•m/s and a velocity of 4 m/s. What is the mass of the bicycle?
Answer:
45kw45_32+675&453try to get it done
Answer:
A: 9 kg
Explanation:
on edge! hope this helps!!~ ∩(︶▽︶)∩
A/An _____ is described as a device used to store electrical energy, usually two conductors separated by an insulator.
Answer: A capacitor.
Explanation:
The capacitor is a passive element that is used in electronics to store electrical energy maintaining an electrical field. The simpler case of a capacitor is the parallel plates capacitor.
It consists of two parallel metal plates separated by a distance D, in this case, the air between the plates works as a dielectric, as the plates do not touch each other and are separated by a dielectric, the charge is stored in the surface plates.
There are a lot of other types of capacitors, the most used in actuality may be the cylindrical one, where instead of parallel plates, it uses two concentric cylinders, and the space between the cylinders is filled with a dielectric/insulator.
in 1-2 complete sentences define "opportunity cost " in your own words
Answer:
Here you go, hope this helps! :)
Explanation:
Opportunity cost is the value of the next best thing you give up whenever you make a decision. It is "the loss of potential gain from other alternatives when one alternative is chosen". ... For example, opportunity cost is how much leisure time we give up to work.
An air-filled capacitor stores a potential energy of 6.00 mJ due to its charge. It is accidentally filled with water in such a way as not to discharge its plates. How much energy does it continue to store after it is filled
This question is incomplete, the complete question is;
An air-filled capacitor stores a potential energy of 6.00 mJ due to its charge. It is accidentally filled with water in such a way as not to discharge its plates. How much energy does it continue to store after it is filled?
(The dielectric constant for water is 78 and for air it is 1.0006.)
Answer: it continue to store 0.07692 mJ after it was filled
Explanation:
Given that;
stored potential energy = 6.00 mJ = 0.006 J
dielectric constant for water K = 78
Energy stored U = Q² / 2C = 0.006 J
C = ∈₀A/d { Air}
C = K∈₀A/d { Water, k = 78 }
so
U = 0.006 / 78
U = 7.6723 × 10⁻⁵J
U = 0.07692 mJ
Therefore it continue to store 0.07692 mJ after it was filled
A Nov-Dec power bill shows that a home uses 1355 kwh over a 30-day period. Find the energy used (in kJ) for the 30-day period.
Answer:
The energy used for the 30-day period is 4878000 kilojoules.
Explanation:
According to the power bill, 1355 kilowatt-hours was used over a 30-day period. A kilowatt-hour is equal to 3600 kilojoules. Then, we calculate the energy used, measured in kilojoules, is determined by simple rule of three:
[tex]E = 1355\,kWh\times \frac{3600\,kJ}{1\,kWh}[/tex]
[tex]E = 4878000\,kJ[/tex]
The energy used for the 30-day period is 4878000 kilojoules.
What happens to the dewpoint temperature of a decreasing mass of air?
Answer:What happens to the dew point temperature of a descending mass of air? As air sinks, it becomes warmer. (Warmer air expands and can hold more water, therefore the dew point may increase.) ... The hot water causes condensation of water vapor as it touches the cooler mirror.
Explanation:
use particle motion to explain what happens when molten steel becomes a steel beam to be used in construction.
Explanation:
A molten steel is in a liquid phase of matter. It has no defined volume of shape at this state. The particles inside this materials in this form is randomized by they are still attached to each other.
On cooling, when the molten steel solidifies and sets into a solid steel beam, the particles take up a fixed position and forms a definite shape and this confers a definite volume on them. The randomized particles stops and forms fixed crystals about their lattice. This way, the beam can carry and support a fixed amount of load.explain why ionizing radiation is dangerous?
Answer:
When the dose is high enough, ionizing radiation causes two types of harm to humans: direct tissue damage and cancer. Direct tissue damage happens when enough molecules are broken apart that the cells simply can no longer function. This can lead to radiation burns, radiation sickness, organ failure, and even death.
Question 3 (1 point)
here were 2cars racing a quarter mile. The green car had a mass of 1200kg and crossed the finish line with a velocity of 53m/s. The red car had
a mass of 1100Kg and crossed the finish line with a velocity of 55m/s.,Which car had the great momentum?
Black car
Blue car
Green car
Red car
Answer:
The green car had the greatest momentum
Explanation:
Momentum
Momentum can be defined as "mass in motion" and is calculated as the product of the mass of the object by its velocity.
Being v the magnitude of the velocity and m the mass of the object, the momentum is calculated with:
p = mv
The green car had a mass of m1=1200 kg and crossed the finish line at v1=53 m/s. Hence, its momentum was:
p1 = 1200 Kg * 53 m/s = 63600 Kg.m/s
The red car had a mass of m2=1100 kg and crossed the finish line at v2=55 m/s. Hence, its momentum was:
p2 = 1100 Kg * 55 m/s = 60500 Kg.m/s
Since p1 > p2, then the green car had the greatest momentum
A boat moves through the water of a river at 8 m/s relative to the water, regardless of the boat's direction. If the water in theriver is flowing at 1.9 m/s, how long does it take the boat to makea round trip consisting of a 260 m displacement downstream followedby a 260 m
Answer:
68.88 m/s
Explanation:
downstream speed = 8+1.9=9.9 m/s
upstream speed = 8-1.9= 6.1 m/s
Therefore, total time taken would be 260/9.9+260/6.1 = 26.26+42.62 =
68.88 m/s
A slide projector projects images on a screen. a) If the slide is 15.5 cm from the lens and the lens has a focal length of 15 cm, how far away is the screen
Answer:
[tex]d_{i}=465 cm=4.65 m[/tex]
Explanation:
Using the thin lens equation, we have:
[tex]\frac{1}{f}=\frac{1}{d_{o}}+\frac{1}{d_{i}}[/tex]
Where:
f is the focal length
d(o) is the distance of the object
d(i) is the distance of the image
[tex]\frac{1}{15}=\frac{1}{15.5}+\frac{1}{d_{i}}[/tex]
[tex]\frac{1}{15}-\frac{1}{15.5}=\frac{1}{d_{i}}[/tex]
[tex]d_{i}=465 cm=4.65 m[/tex]
Therefore, the screen is at 465 cm.
I hope it helps you!
A 6.5 kg rock thrown down from a 120m high cliff with initial velocity 18 m/s down. Calculate
the following ATTENTION：using the energy/work formulae only: 3.The kinetic energy of the Rock half way down ？ 4.the speed of the Rock half way down？
5.The speed of the Rock as it hits the ground？
Answer:
See the answers below.
Explanation:
In order to solve this problem we must use the principle of energy conservation. Which tells us that the energy of a body will always be the same regardless of where it is located. For this case we have two points, point A and point B. Point A is located at the top at 120 [m] and point B is in the middle of the cliff at 60 [m].
[tex]E_{A}=E_{B}[/tex]
The important thing about this problem is to identify the types of energy at each point. Let's take the reference level of potential energy at a height of zero meters. That is, at this point the potential energy is zero.
So at point A we have potential energy and since a velocity of 18 [m/s] is printed, we additionally have kinetic energy.
[tex]E_{A}=E_{pot}+E_{kin}\\E_{A}=m*g*h+\frac{1}{2}*m*v^{2}[/tex]
At Point B the rock is still moving downward, therefore we have kinetic energy and since it is 60 [m] with respect to the reference level we have potential energy.
[tex]E_{B}=m*g*h+\frac{1}{2}*m*v^{2}[/tex]
Therefore we will have the following equation:
[tex](6.5*9.81*120)+(0.5*6.5*18^{2} )=(6.5*9.81*60)+(0.5*6.5*v_{B}^{2} )\\3.25*v_{B}^{2} =4878.9\\v_{B}=\sqrt{1501.2}\\v_{B}=38.75[m/s][/tex]
The kinetic energy can be easily calculated by means of the kinetic energy equation.
[tex]KE_{B}=\frac{1}{2} *m*v_{B}^{2}\\KE_{B}=0.5*6.5*(38.75)^{2}\\KE_{B}=4878.9[J][/tex]
In order to calculate the velocity at the bottom of the cliff where the reference level of potential energy (potential energy equal to zero) is located, we must pose the same equation, with the exception that at the new point there is only kinetic energy.
[tex]E_{A}=E_{C}\\6.5*9.81*120+(0.5*9.81*18^{2} )=0.5*6.5*v_{C}^{2} \\v_{c}^{2} =\sqrt{2843.39}\\v_{c}=53.32[m/s][/tex]