The acceleration is defined as:
[tex]a=\frac{v_f-v_0}{t}[/tex]where vf is the final velocity, v0 is the initial velocity and t is the time. In this case we have:
The initial velocity is 80 mph
The final velocity is 0 mph (since the car stops)
The time it takes to slow down is 6 seconds.
Before we can do the calculation, we need to convert the velocity to appropriate units; let's write the initial velocity in ft/s units. To do this we need to remember that 1 mile is equal to 5280 ft and one hour is equal to 3600 s, then we have:
[tex]80\frac{mi}{h}\cdot\frac{5280\text{ ft}}{1\text{ mi}}\cdot\frac{1\text{ h}}{3600\text{ s}}=117.33\frac{ft}{s}[/tex]Hence the initial velocity is 177.33 ft/s.
Now that we have all the values we need, we plug them in the equation for the acceleration:
[tex]\begin{gathered} a=\frac{0-117.33}{6} \\ a=-19.56 \end{gathered}[/tex]Therefore, the acceleration is -19.56 feet per second per second. Note: The minus sign indicates that the car is slowing down.
Two points ___________ create a line.A. sometimesB. neverC. alwaysD. not enough information
According to the Euclidean Postulates, a straight line segment can be drawn joining any two points.
Therefore, the answer is:
[tex]C)\text{ Always}[/tex]A power company transmits current through a 240,000 V transmission line. This voltage is stepped down at an area substation to 40,000 V by a transformer that has 940 turns on the primary coil. How many turns are on the secondary of the transformer? _________turns
Given:
The voltage in the transmission line is: V = 240000 v
The stepped-down voltage is: Vs = 40000 v
The turns of the primary coil of the transformer are: Np = 940
To find:
The turns of the secondary coil of the transformer.
Explanation:
The voltage in a transmission line is used to step down by using the transformer. Thus, the primary voltage of the transformer will be the voltage in the transmission line.
Thus, Vp = V = 240000 v
The primary voltage Vp, the secondary voltage Vs, the primary turns on the coil Np and the secondary turns on the coil Ns are related as:
[tex]\frac{V_p}{V_s}=\frac{N_p}{N_s}[/tex]Rearranging the above equation, we get:
[tex]\begin{gathered} N_s=N_p\frac{V_s}{V_p} \\ \\ N_s=940\times\frac{40000\text{ v}}{240000\text{ v}} \\ \\ N_s=940\times\frac{4}{24} \\ \\ N_s=156.67 \\ \\ N_s\approx157 \end{gathered}[/tex]Final answer:
The number of turns on the secondary coil of the transformer are approximately 157.
Calculate the kinetic energy of a roller coaster that has a mass of 1,778.6 kg and is traveling with a velocity to 24.5 m/s at the bottom of the first hill.
Given:
The mass of the roller coaster is m = 1778.6 kg
The velocity of the roller coaster is v = 24.5 m/s
To find the kinetic energy of the roller coaster.
Explanation:
The formula to calculate the kinetic energy is
[tex]K\mathrm{}E\text{. =}\frac{1}{2}mv^2[/tex]Substituting the values, the kinetic energy will be
[tex]\begin{gathered} K\mathrm{}E\text{. =}\frac{1}{2}\times1778.6\times(24.5)^2 \\ =533802.325\text{ J} \end{gathered}[/tex]Final Answer: The kinetic energy of the roller coaster is 533802.325 J.
carts, bricks, and bands
3. Which statement describes the effect of a doubling of force upon the acceleration of a cart of constant mass?
a. Doubling the force will cause the acceleration to be twice the original value.
b. Doubling the force will cause the acceleration to be one-half the original value.
c. Doubling the force will cause the acceleration to be four times the original value.
d. Doubling the force will cause the acceleration to be one-fourth the original value.
The statement that describes the effect of a doubling a force at a constant mass is "doubling the force will cause the acceleration to be twice the original value.
The correct answer is option A.
What is the applied force on an object?
The force applied on object is obtained by multiplying the mass and acceleration of the object.
According to Newton's second law of motion, the force exerted on an object is directly proportional to the product of mass and acceleration of the object.
Also, the applied force is directly proportional to the change in the momentum of the object.
Mathematically, the force acting on object is given as;
F = ma
a = F/m
where;
a is the acceleration of the objectm is the mass of the objectF is the applied forceAt a constant mass;
F₁/a₁ = F₂/a₂
When the force is doubled, the acceleration of the object is given as;
a₂ = F₂a₁/F₁
a₂ = (2F₁ x a₁) / F₁
a₂ = 2a₁
Thus, when the force on the cart is doubled and the mass is constant, the acceleration of the cart will double as well.
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Will mark as Brainlist!
Which of the following best represents R= A - B ?
Please help, it’s due soon!
The option (C) best represents the R = A- B
What is vector in mathematics?A vector in mathematics is a quantity that not only expresses magnitude but also motion or position of an object in relation to another point or object. Euclidean vector, geometric vector, and spatial vector are other names for it.
In mathematics, a vector's magnitude is defined as the length of a segment of a directed line, and the vector's direction is indicated by the angle at which the vector is inclined.
What are the components in vector quantity?A vector primarily consists of two elements, the horizontal component and the vertical component. The horizontal component's value is cosθ, and the vertical component's value is sinθ.
There are two types of vector multiplication, they are dot products and cross products.
Learn more about vector here :
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I want to know if I’m doing this correctly, and if not, then what would be the best process to do solve it?
Given
[tex]3\times10^{-10}m^{}[/tex]
Factor Name Symbol
10-1 deci d
10-2 centi c
10-3 milli m
10-6 micro µ
10-9 nano n
10-12 pico p
10-15 femto f
10-18 atto a
10-21 zepto z
10-24 yocto y
a. nanometers
0.3 nm
[tex]3\times10^{-1}nm^{}[/tex]b. picometers
300 pm
[tex]3\times10^2pm[/tex]name the quatity whose SI unit is j/kg/°c
Answer:
Explanation:
Specific heat:
[ c ] = 1 J / (kg·°C)
When x = –4, what is the value of g(x)? g(x)=-5x+3 help please
Replace the value x=-4 into the expression for g(x) and simplify, as follow:
[tex]\begin{gathered} g(-4)=-5(-4)+3 \\ g(-4)=20+3 \\ g(-4)=23 \end{gathered}[/tex]Hence, g(-4) = 23
how far away is a star if it takes light 12.5 years to reach the earth?
b. Andrea has a particularly old bike, and she has not lubricated the chain orgears. This causes friction inside the gears as she rides. She begins coasting onflat ground at a speed of 10 m/s, and after a few seconds is only going 8 m/s.How much energy has been converted to heat? (1 point) (The combined mass is 50kg)c. Andrea is going 10 m/s toward a hill. She coasts up the hill without pedaling. Iffriction causes 10% of her energy to be converted to heat inside the gears, howhigh up the hill will she be able to coast? (2 points)
b.
The energy converted in heat is the change in kinetic energy, that is, the kinetic energy lost is the same as the heat.
The kinetic energy is given by:
[tex]K=\frac{1}{2}mv^2[/tex]The change in kinetic energy is given by:
[tex]K_f-K_0=\frac{1}{2}mv^2_f-\frac{1}{2}mv^2_0[/tex]Plugging the values given we have that:
[tex]\begin{gathered} K_f-K_0=\frac{1}{2}(50)(8)^2-\frac{1}{2}(50)(10)^2 \\ =-900 \end{gathered}[/tex]Hence Andrea has lost 900 J of energy and therefore 900 J is converted to heat.
c.
We know that the energy is conserved, in this case this means that the initial kinetic energy has to be equal to the energy lost by heat in the gears and the potential energy gained by climbing up the hill, that is:
[tex]K=Q+U[/tex]where K is the kinetic energy, Q is the heat and U is the potential energy.
We know that 10% of her energy is converted in heat, this means that:
[tex]Q=0.1K[/tex]and hece we have:
[tex]\begin{gathered} K=0.1K+U \\ U=0.9K \end{gathered}[/tex]the potential energy is given by:
[tex]U=mgh[/tex]then we have that:
[tex]mgh=0.9(\frac{1}{2}mv^2)[/tex]Plugging the values given and solving for h we have:
[tex]\begin{gathered} (50)(9.8)h=0.9(\frac{1}{2}(50)(10^2)) \\ 490h=2250 \\ h=\frac{2250}{490} \\ h=4.59 \end{gathered}[/tex]Therefore Andrea will be able to climp up to 4.59 meters
Please help me with this! (Sadly my previous tutor couldn't help me with this)
a.
The free body diagram (not at scale) for each crate is shown below:
b.
In this case we know that the force is just sufficient to keep the crates from sliding, this means that the acceleration of the system is zero.
From the free body diagram and Newton's second law we have that for the 45 kg crate that:
[tex]\begin{gathered} T-W=0 \\ T=W \\ T=(45)(9.8) \\ T=441 \end{gathered}[/tex]For the 35 kg crate the equations of motion would be:
[tex]\begin{gathered} F+f_f-T=0 \\ N-W^{\prime}=0 \end{gathered}[/tex]but we know that the force of friction is given by:
[tex]F_f=\mu N[/tex]and from the second equation of motion we have that:
[tex]\begin{gathered} N=W^{\prime} \\ N=(35)(9.8) \\ N=343 \end{gathered}[/tex]Then we have that:
[tex]\begin{gathered} F+F_f-T=0 \\ F+343\mu-441=0 \end{gathered}[/tex]Since the crates are not moving we need to use the static coefficient of friction, then:
[tex]\begin{gathered} F+343\mu-441=0 \\ F+343(0.5)-441=0 \\ F+171.5-441=0 \\ F-269.5=0 \\ F=269.5 \end{gathered}[/tex]Therefore the force applied is 269.5 N
c.
The diagram in this case is:
d.
In this case we know that the 35 kg is sliding to the right at constant velocity, this means that the acceleration for the system is zero. (Notice that the difference with the previous case is that the friction points to the left)
From the discussion in part b we know that for the 45 kg block:
[tex]T-W=0[/tex]and then:
[tex]T=441[/tex]For the 35 kg we have that:
[tex]\begin{gathered} F-F_f-T=0 \\ N-W^{\prime}=0 \end{gathered}[/tex]from the previos discussion we know that:
[tex]N=343[/tex]and since in this case the crates are moving we need to use the kinetic coefficient of friction, then we have:
[tex]\begin{gathered} F-F_f-T=0 \\ F-(0.3)(343)-441=0 \\ F-102.9-441=0 \\ F-543.9=0 \\ F=543.9 \end{gathered}[/tex]Therefore in this case the force applied is 543.9 N
e.
In this case the free body diagram is:
f.
Since the crates are moving with an accelearion of 0.5 m/s^2 we have for the 45 kg crate that:
[tex]T-W=ma[/tex]from where:
[tex]\begin{gathered} T-(9.8)(45)=(45)(0.5) \\ T-441=22.5 \\ T=441+22.5 \\ T=463.5 \end{gathered}[/tex]For the 35 kg crate we have that:
[tex]\begin{gathered} F-F_f-T=m^{\prime}a \\ N-W^{\prime}=0 \end{gathered}[/tex]from the previous discussion we know that N=343, plugging this in the first equation we have:
[tex]\begin{gathered} F-(0.3)(343)-463.5=(35)(0.5) \\ F-102.9-463.5=17.5 \\ F-566.4=17.5 \\ F=566.4+17.5 \\ F=583.9 \end{gathered}[/tex]Therefore the force applied in this case is 583.9 N
Megan kicks a soccer ball with a mass of 2 kg. The ball leaves the ground moving 50 meters per second. What is the kinetic energy of the ball?
ANSWER
[tex]2500J[/tex]EXPLANATION
The kinetic energy of a body is the energy it possesses due to its motion and it can be found by applying the formula:
[tex]E=\frac{1}{2}mv^2[/tex]where m = mass, v = velocity
From the question:
[tex]\begin{gathered} m=2\text{ kg} \\ v=50\text{ m/s} \end{gathered}[/tex]Therefore, the kinetic energy of the ball is:
[tex]\begin{gathered} E=\frac{1}{2}\cdot2\cdot50^2 \\ E=2500J \end{gathered}[/tex]You turn a corner and are driving up asteep hill. Suddenly, a small boy runs out on the street chasing a ball. You slam on the brakes and skid to astop leaving a 50-foot-long skid mark on the street. The boy calmly walks away but a policemen watching fromthe sidewalk walks over and gives you a speeding ticket. He points out that the speed limit on this street is 25mph. After you recover your wits, you begin to examine the situation. You determine that the street makes anangle of 25◦with the horizontal and that the coefficient of static friction between your tires and the street is0.80. You also find that the coefficient of kinetic friction between your tires and the street is 0.60. Your car’sinformation book tells you that the mass of your car is 1600 kg. You weigh 140 lbs.
Given data:
Total displacement of the car;
[tex]s=50\text{ ft}[/tex]Speed limit;
[tex]v_m=25\text{ mph}[/tex]The angle of street from horizontal;
[tex]\theta=25\degree[/tex]Coefficient of static friction;
[tex]\mu_s=0.80[/tex]Coefficient of kinetic friction;
[tex]\mu_k=0.60[/tex]Mass of the car;
[tex]M=1600\text{ kg}[/tex]Weight of the man;
[tex]W=140\text{ lbs}[/tex]The kinetic friction force is given as,
[tex]F_k=\mu_k(M+m)g\cos \theta[/tex]Here, m is the mass of the man and g is the acceleration due to gravity.
The acceleration of the car driving up a steep hill is given as,
[tex]\begin{gathered} (M+m)g\sin \theta+F_k=(M+m)a \\ (M+m)g\sin \theta+\mu_k(M+m)g\cos \theta=(M+m)a \\ g\sin \theta+\mu_kg\cos \theta=a \end{gathered}[/tex]Substituting all known values,
[tex]\begin{gathered} (32\text{ ft/s}^2)\times\sin (25\degree)+0.6\times(32\text{ ft/s}^2)\times\cos (25\degree)=a \\ \approx30.92\text{ ft/s}^2 \end{gathered}[/tex]The velocity of the car is given as,
[tex]v^2=u^2-2as[/tex]Here, v is the final velocity (v=0, as the car stops), and u is the initial velocity.
The initial velocity of the car is given as,
[tex]u=\sqrt[]{v^2+2as}[/tex]Substituting all known values,
[tex]\begin{gathered} u=\sqrt[]{0^2+2\times(30.92\text{ ft/s}^2)\times(50\text{ ft})} \\ \approx55.61\text{ ft/s} \\ \approx37.91\text{ mph} \end{gathered}[/tex]Therefore, your speed is greater than the speed limit. Thus, you can not fight the ticket in the court.
A total of 8.0 joules of work is done when a constant horizontal force of 2.0 newtons to the left is used to push a 3.0-kilogram box acrossa counter top. Determine the total horizontal distance the box moves.
ANSWER
4 meters
EXPLANATION
Given:
• Work = 8.0 J
,• Force = 2.0 N
,• Mass of the box = 3.0 kg
Unknown:
• Distance the box moves
Work is the product of the applied force in the direction of motion and the distance an object moves,
[tex]W=F\cdot d[/tex]In this case, a box is pushed horizontally with a force of 2N producing a work of 8J. Solve the equation above for d,
[tex]d=\frac{W}{N}=\frac{8.0J}{2.0N}=4m[/tex]Hence, the horizontal distance the box moves is 4 meters.
An object initially at rest experiences an acceleration of 9.8 m/s2. How much time will it take it to achieve a velocity of 49 m/s? v = vo + at
Given data:
* The initial velocity of the object is 0 m/s.
* The final velocity of the object is 49 m/s.
* The acceleration of the object is,
[tex]a=9.8ms^{-2}[/tex]Solution:
The time taken by the object to achieve the final velocity is,
[tex]v=v_o+at[/tex]where v is the final velocity, v_o is an initial velocity, a is an acceleration, and t is the time taken by the object to acquire the final velocity,
Substituting the known values,
[tex]\begin{gathered} 49=0+9.8\times t \\ 49=9.8t \\ t=\frac{49}{9.8} \\ t=5\text{ s} \end{gathered}[/tex]Thus, the time taken by the object to acqurie the final velocity is 5 seconds.
Solve: What work is done when 3.0 C is moved through an electric potential difference of 1.5 V?1) 0.5 J2) 2.0 J3) 4.0 J4) 4.5 J
We know that the work done in an electric potential difference is
[tex]\begin{gathered} W=V\cdot Q \\ W=1.5V\cdot3.0C \\ W=4.5J \end{gathered}[/tex]Therefore, the work done is 4.5 J.What are the units for buoyant force?
Answer Unit of Buoyant Force The unit of the buoyant force is the Newton (N). = Here, F= buoyant force
Explanation:
i hope this helpes
If a bus is traveling at 12m/s and a passenger on the bus is walking to the back of the bus at a velocity of 5m/s, what is the relative velocity of the passenger relative to the ground?
The relative velocity is 17m/s.
The relative velocity of the passenger relative to the ground can be found by applying the concept of relative motion.
speed of bus (vb)=12m/s
speed of passenger inside the bus(vp)= 5m/s opposite to the speed of bus
speed of passenger relative to the ground = v
v= vb+vp
v= 12+(-5), since passenger is traveling in opposite direction
v=7m/
Therefore, the velocity of passenger relative to the ground is 7m/s.
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55
3. A ball is rolling at a rate of -2.4 m/s.
The ball then rolls down a hill, causing it to accelerate to a velocity of
8.6 m/s in 4.5 seconds time. What is the acceleration of the ball?
Carol Gillian theorized that when it comes to a perspective of Justice,males per socialized for a blank environment while females are socialized for a blank environment
Answer: men = work environment , women = home environment
Explanation: Gillian proposed that women come to prioritize as “ethics of care” and men as “ethics of justice”.
In one or two sentences, explain how you would draw the particles in a gas.
Explanation
In gases the particles move rapidly in all directions, frequently colliding with each other and the side of the container
so
I would draw it with the particles separated moving and colliding with the others
I hope this helps you
Which of the following is an example of Newton's third law of motion?A. A skydiver slows down when her parachute opens.B. A grocery cart moves forward when it is pushed.C. A cannon recoils backwards when it is fired.D. A rolling rock slows down due to friction.
Explanation:
The third law of Newton says that when an object exerts a force on a second object, the first object experiences an equal and opposite force that is exerted by the second object.
So, the example that shows this law is:
C. A cannon recoils backward when it is fired.
Because the cannon e
40) Climbing the Empire State Building A new record for running the stairs of the Empire State Building was set on February 4, 2003. The 86 flights, with a total of 1576 steps, was run in 9 minutes and 33 seconds. If the height gain of each step was 0.20 m, and the mass of the runner was 70.0 kg, what was his average power output during the climb? Give your answer in both watts and horsepower.
The power is given by:
[tex]P=\frac{W}{t}[/tex]where W is the work and t is the time.
We know that the work done is related to the gravitational potential energy by:
[tex]W=mg(y_f-y_0)[/tex]where yf is the final height of the object and y0 is the initial height.
Now, in this case we have a total of 1576 steps, each of them with a height of 0.2 meters that means that the total height gained is:
[tex](1576m)\cdot0.2=315.2\text{ m}[/tex]This in turns means that the work done is:
[tex]W=(70\operatorname{kg})(9.8\frac{m}{s^2})(315.2m)=216227.2\text{ J}[/tex]Now, the time it takes to achieve this is 9 minutes 33 seconds, this is the same as:
[tex]9(60)+33=573\text{ s}[/tex]Finally we use the power formula:
[tex]P=\frac{216227.2\text{ J}}{573\text{ s}}=377.36\text{ W}[/tex]Now we need to remember that 1 Hp is equal to 745.7 W, then we have that this is the same as:
[tex]377.36\text{ W}\cdot\frac{1\text{ Hp}}{745.7\text{ W}}=0.506[/tex]Therefore the power to make that climb is 377.36 W or 0.506 Hp
I’m confused about which electromagnetic waves have the lowest frequency
The eletromagnetic wave that has the highest frequency is the gamma rays. It also has the highest energy and shortest wavelengths.
On the other hand, the type of eletromagnetic wave that has the lowest frequency, lowest energy and longest wavelength is radio waves.
You decide to roll a 0.10 kg ball across the floor so slowly that it will have a small momentum and a large de Broglie wavelength. If you roll it at 1.4x1^-3 m/s, what is its wavelength? Express your answer to two significant figures and include the appropriate units. How will the answer from above compare with the de Broglie wavelength of the high-speed electron that strikes the back face of one of the early models of a TV screen at 1/10 the speed of light (2x10^-11 m) ?
ANSWER:
(a) 4.73*10^-30 m
(b) 2.37*10^-19 times smaller
STEP-BY-STEP EXPLANATION:
Given:
Mass of ball = m = 0.10 kg
Speed of ball = v = 1.4x10^-3 m/s
(a)
Since, de Broglie wavelength is given by:
[tex]\lambda=\frac{h}{mv}[/tex]Where, h is the Plank's Constant ( h = 6.626x10^-34 kg m^2/s). Therefore, de Broglie wavelength of the ball will be:
[tex]\begin{gathered} \lambda=\frac{6.626\cdot10^{-34}}{0.10\cdot1.4\cdot10^{-3}} \\ \lambda_{\text{ball}}=4.73\cdot10^{-30} \end{gathered}[/tex](b)
[tex]\begin{gathered} \lambda_{electron}=2\cdot10^{-11} \\ \frac{\lambda_{\text{ball}}}{\lambda_{electron}}=\frac{4.73\cdot10^{-30}}{2\cdot10^{-11}} \\ \frac{\lambda_{\text{ball}}}{\lambda_{electron}}=2.37\cdot10^{-19} \end{gathered}[/tex]It means that the wavelength of the ball is 2.37*10^-19 times smaller
In order to hear a sound, even though there is an obstacle between you and the source, the sound wave must:A.diffract.B.refract.C.shorten.D.reflect.
We will have the following:
The sound must diffract. [Option A]
Given a DC battery of voltage, V = 4.00 V connected to a resistor R with a current I = 3.00 A through the resistor. What power is in this circuit? 15.5 W 12.0 W 39.4 W 45.5 W 8.88 W
12.0 W
Explanation
Electric power is the rate, per unit time, at which electrical energy is transferred by an electric circuit. to find the power in the circuit we need to use the expression:
[tex]P=IV[/tex]where P is the powe I is the current and V is the voltage
Step 1
a)Let
[tex]\begin{gathered} I=\text{ 3 Amperes} \\ V=4.0\text{ volts} \end{gathered}[/tex]b) now,replace
[tex]\begin{gathered} P=IV \\ P=3\text{ A*4 V} \\ P=12\text{ W} \end{gathered}[/tex]therefore, the answer is
12.0 W
I hope this helps you
I need help with some questions to study them for midterms!
The correct answer is option C.
The acceleration of an object is defined as the time rate of change of velocity. Velocity is a vector and has magnitude and direction. The change velocity may mean either a change in magnitude or change in direction or both.
Thus an object can have acceleration even when the speed is constant. For example, an object in a circular motion.
Thus the correct answer is option C.
PLEASE HELPPPPPPPPPPPPPPPPPPPPPPP
Answer:
right answer is death valley
Explanation:
because it is close to surface gravitational field
mexico
cus its the farthest
In a chosen coordinate system, the position of an object in motion can have negative values.Question 2 options:TrueFalse
True
Explanations:The position of an object can take any sign, it can be negative, zero or positive. This depends on the coordinate system chosen.
The position of an object (whether moving or static) is specified with respect to a frame of reference, and can be positive, zero or negative depending on the coordinate system chosen
Therefore, we can conclude that, in a chosen coordinate system, the position of an object in motion can have negative values.