Answer:
voltraise the potential of electronsIt is a much more efficient mode of transmitting electricity than direct current does not movesA car of 900 kg mass is moving at the velocity of 60 km/hr. It is brought into rest at 50 meter distance by applying a brake. Now, calculate the force required to stop the car.
Answer: [tex]-2502N[/tex]
Explanation:
[tex](V_2)^2=(V_1)^2+2ad[/tex]
where;
[tex]V_2[/tex] = final velocity = 0
[tex]V_1[/tex] = initial velocity = 60 km/h = 16.67 m/s
[tex]a[/tex] = acceleration
[tex]d[/tex] = distance
First all of, because acceleration is given in m/s and not km/h, you need to convert 60km/h to m/s. Our conversion factors here are 1km = 1000m and 1h = 3600s
[tex]60km/h(\frac{1000m}{1km} )(\frac{1h}{3600s} )=16.67m/s[/tex]
Solve for a;
[tex](V_2)^2=(V_1)^2+2ad[/tex]
Begin by subtracting [tex](V_1)^2[/tex]
[tex](V_2)^2-(V_1)^2=2ad[/tex]
Divide by 2d
[tex]\frac{(V_2)^2-(V_1)^2}{2d} =a[/tex]
Now plug in your values:
[tex]a=\frac{(0)^2-(16.67 m/s)^2}{2(50m)}[/tex]
[tex]a=\frac{0-277.89m^2/s^2}{100m}[/tex]
[tex]a=-2.78m/s[/tex]
If you're wondering why I calculated acceleration first is because in order to find force, we need 2 things: mass and acceleration.
[tex]F=ma[/tex]
m = mass = 900kg
a = acceleration = -2.78m/s
[tex]F=(900kg)(-2.78m/s)\\F=-2502N[/tex]
It's negative because the force has to be applied in the opposite direction that the car is moving.
4. In a long distance race, the athletes were expected to take four rounds of the track such that the line of finish was same as the line of start. Suppose the length of the track was 200m. What is the total distance to be covered by the athletes? What is the displacement of the athletics when they touch the finish line?
Answer:
The total distance to be covered by the athletes is 800 m
The displacement of the athletes when they touch the finish line is zero.
Explanation:
Given;
Length of the track, L = 200m
the Length of the track for a single round = 200 m
(a) Distance is a scalar quantity which has only magnitude;
If the athletes were expected to take four rounds of the track, then the total distance = 4 x 200 m = 800 m
(b) Also, if the line of finish was same as the line of start, then displacement of the athletes when they touch the finish line is zero (0 meters). This is because displacement has both magnitude and direction. Once the athlete returns to his starting point, his displacement at that point is zero.
The ratio of the potential difference across a conductor to the current in the conductor is called
A) conductivity
B) resistance
C) charge
D) power
Answer:
The ratio of the potential difference across a metallic conductor to the current in the conductor is known as.
B. Resistance.
Explanation:
According to ohms law " the current passing through a conductor is directly proportional to the potential difference between the ends provided the temperature of the wire remains constant".
What is resistance ?
Resistance is a measure of the opposition to current flow in an electrical circuit
what is a resistor ?
a resistor is a n electric conductor which forms resistance to free flow of electric current, the resistance is measured in Ω
The ratio of the potential difference across the conductor to the current is called resistance
What is Resistance?It is defined as the ratio of the potential difference across the conductor to the current. The resistance is measured in Ω.
[tex]R = \dfrac VI[/tex]
Where,
[tex]R[/tex] - resistance
[tex]V[/tex]- voltage (Potential difference)
[tex]I[/tex] - current
Therefore, the ratio of the potential difference across the conductor to the current is called resistance.
To know more about resistance.
https://brainly.com/question/4289257
What class lever is a
1.Pencil Sharpener
2.Tennis racket
3. Hole puncher
4. Can opener
should be 1
Explanation:
because what do you use in class and has a lever
name and describe the process that fuels the sun
Answer:
The Sun derives all its energy from a fusion cycle. In that process, tiny hydrogen molecules combine into a continuous proton-proton chain to create larger helium nuclei. The above figure illustrates the fusion of hydrogen into helium.
Explanation:
Hope this helps.
Answer:
nuclear fusion
Explanation:
In this process, small hydrogen molecules fuse together to form bigger helium nuclei in a continuous proton-proton chain.
Which of the following would accurately label the X axis?
Answer: Distance
I’m not sure if it is correct, but I am pretty sure it is......
I hope this helps :)
why is a layer of pollution in the air more visible in winter than summer
Answer:
During winters the planetary boundary layer is thinner as the cooler air near the earth's surface is dense. The cooler air is trapped under the warm air above that forms a kind of atmospheric 'lid'. This phenomenon is called winter inversion
Explanation:
A ladder is at rest with Oct upper end against a wall and its lower end on the ground.A worker is about to climb it.When is it more likly to slip
Answer: When the worker is on the top rung
Explanation: When the ladder was initially resting on the wall, the torque from the normal reaction on ladder from the horizontal surface is equal to the torque from the vertical surface on ladder.
The weight of the worker produces a torque which is in the direction of the torque from the normal reaction on ladder, produced by the vertical surface. Therefore for the ladder to stay in rotational equilibrium, the torque on ladder from the normal reaction produced by the horizontal surface must increase.
This increase is possible when the worker is on the lower rung, but as the worker goes high, the magnitude of normal reaction from the vertical surface would increase, thereby increasing the risk of slipping of ladder.
How does friction affect velocity
Answer:
It slows it down.
Explanation:
Higher the velocity, higher the friction. Friction is the force OPPOSITE to whatever the force is going.
A longitudinal wave moves energy that is to the direction of the wave’s movement.
Answer:
In longitudinal waves, the displacement of the medium is in the same direction as, or the opposite direction to, the direction of propagation of the wave. Mechanical longitudinal waves are also called compressional or compression waves because they produce compression and rarefaction of a medium when traveling through the medium. They are also called pressure waves, because they produce increases and decreases in pressure of the medium. Sound waves is an example of longitudinal wave.
Answer:
parallel
Explanation:
i got it right on the test :)
An iron nail does not pick up paper clips as a magnet would.
Answer:
Because even if iron is magnetic its not a magnet it self unless rubbed a magnetic object
Why do you think sound travels faster in steel than it does in wood? (Hint: Think about the densities of the two materials, and how the particles might be arranged.)
Answer:
If sound waves of the same energy were passed through a block of wood and a block of steel, which is more dense than the wood, the molecules of the steel would vibrate at a slower rate. Sound moves faster through denser air because the molecules are closer together in dense air and sound can be more easily passed on.
Explanation:
What’s the resistance in the circuit
Answer:
I = 0.75 A
Explanation:
The question is not to calculate the resistance, but to calculate the current. (The resistance is already given by the value of 2 Ohm).
U = I * R
I = U / R
with U = 1.5 V and R = 2 Ohm
I = 1.5 / 2
I = 0.75 A
if an object in motion, experiences a net zero unbalanced force, the the body
1) will always remain at rest
2) cannot remain at rest
3) can be accelarated
4) moves with constant velocity
please choose the suitable option and give an explanation (not necessary) .
Answer:
4) moves with constant velocity
Explanation:
If an object is in motion, three things can happen:
1. The object slows down in speed.
This means a net force is needed to be able to slow the object down in speed.
2. The object increases in speed.
This means a net force is needed to be able to increase the speed of the object.
3. The object remains in motion at the same speed.
No net zero unbalanced force is needed.
This is the given situation. So this is the right answer.
To complete a project, 200,000 Joules of work is needed. The time taken to complete the project is 20 seconds. How much power is needed?
Answer:
10,000
Explanation:
200,000/20 = power needed
200,000/20 = 10,000
Hope this Helps!
Answer:
10,000 Watts
Explanation:
Power is the ratio of work to time, or work over time. It can be found using the following formula.
p=w/t
where p is the power, w is the work, and t is the time.
The project needed 200,000 Joules, and it took 20 seconds to complete the project. Therefore, w=200,000 and t=20. Substitute these values into the formula.
p=200,000/20
Divide
p=10,000
Add appropriate units. The units for power is Watts.
p=10,000 Watts
10,000 Watts of power is needed.
What adjustments to an electromagnet that causes the electromagnet to lose a strength
Explanation:
1) reduction in current
2)less no. of coils per unit length
3) removal of soft iron core
A hollow cylindrical (inner radius = 1.0 mm, outer radius = 3.0 mm) conductor carries a current of 80 A parallel to its axis. This current is uniformly distributed over a cross section of the conductor. Determine the magnitude of the magnetic field at a point that is 2.0 mm from the axis of the conductor.
Answer:
The magnetic field is [tex]B = 3 mT[/tex]
Explanation:
From the question we are told that
The inner radius is [tex]r_i = 1.00 mm =1*10^{-3} \ m[/tex]
The outer radius is [tex]r_2 = 3.00 \ mm = 3.0 *10^{-3} \ m[/tex]
The distance from the axis of the conductor is [tex]d =2.0 \ mm = 2.0 *10^{-3} \ m[/tex]
The current carried by the conductor is [tex]I = 80 A[/tex]
According to Ampere's circuital law , the magnetic field at a point that is [tex]r_3[/tex] from the axis of the conductor
[tex]B = \frac{\mu_oI}{2 \pi d } [\frac{d - r_1}{r_2 -r_1} ][/tex]
Where [tex]\mu_o[/tex] is the permeability of free space with a value of [tex]\mu_o = 4 \pi *10^{-7} N/A^2[/tex]
substituting values
[tex]B = \frac{(4 \pi *10^{-7})(80)}{2 * 3.142 * 2 *10^{=3} } [\frac{(2^2 - 1 ^2 )*10^{-3}}{(3^2 - 1^2) *10^{-3}} ][/tex]
[tex]B = 3 mT[/tex]
Force = 65 kg x 3 m/s =
What is the answer?
What units do you use for your end result?
Answer:
multiply 65kg and 3m/s^2
to get 195kgm/s
or 195N
wait is that 3m/s or 3m/s^2?
An atom of an element can be modeled in several ways. The diagram below shows one model of an atom.
What can be located in the lighter shaded region surrounding the nucleus?
A.
electrons
B.
neutrons
C.
molecules
D.
protons
STUDY ISLAND
Answer:
Electrons
Explanation:
Protons and Neutrons are found within the nucleus and while electrons are much smaller and found outside the nucleus
Answer:
c
Explanation:
What is the current through a 11v bulb with a power of 99w
Answer:
9.01amp
Explanation:
Power = V^2/R
Given that v = 11volts, P = 99watts
99 = 11^2/R
11×11 = 99R
121= 99R
R = 121/99
R= 1.22ohms
From ohms Law; V = IR
11volts = I × 1.22ohms
I = 11/1.23
I = 9.01 amp
please help its in science CER, 30 points
Answer:We have seasons because the earth is tilted (wonky) as it makes its yearly journey around the sun. The Earth's axis is tilted at an angle of 23.5 degrees. This means that the Earth is always "pointing" to one side as it goes around the Sun.
Explanation:
got this from the internet
The persistence of vision for normal eye is
Answer:
The answer is 1/16
Explanation:
1. Persistence of vision refers to the optical illusion that occurs when visual perception of an object does not cease for some time after the rays of light proceeding from it have ceased to enter the eye. 2. The persistence of vision for normal eye is 1/16 if a second.
What is the answer to this question?
Answer:
C
Explanation:
The temperature of an object does not change when it is going through a phase change, since there is a single specific point on the temperature gradient where that change occurs. Once the phase change has occurred, the water's temperature can continue to change in that direction, but during the phase change it does not. Hope this helps!
Answer: The answer is C
Explanation:
Hope it helps :)
Se golpea una pelota de golf de manera que su velocidad inicial forma un ángulo de 45° con la horizontal. La pelota alcanza el suelo a 180 metros del punto en que se lanzó. Calcula su velocidad inicial y el tiempo que ha Estado en el aire
Answer:
42m/s
6.06s
Explanation:
To find the initial velocity and time in which the ball is fling over the ground you use the following formulas:
[tex]x_{max}=\frac{v_o^2sin(2\theta)}{g}\\\\x_{max}=vt_{max}[/tex]
θ: angle = 45°
vo: initial velocity
g: gravitational constant = 9.8m/s^2
x_max: max distance = 180 m
t_max: max time
by replacing the values of the parameters and do vo the subject of the first formula you obtain:
[tex]v_o=\sqrt{\frac{gx_{max}}{sin(2\theta)}}\\\\v_o=\sqrt{\frac{(9.8m/s^2)(180m)}{sin(2(45\°))}}=42\frac{m}{s}[/tex]
with this value of vo you calculate the max time:
[tex]t_{max}=\frac{x_{max}}{v}=\frac{x_{max}}{v_ocos(45\°)}\\\\t_{max}=\frac{180m}{(42m/s)cos(45\°)}=6.06s[/tex]
hence, the initial velocity of the ball is 42m/s and the time in which the ball is in the air is 6.06s
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TRANSLATION:
Para encontrar la velocidad inicial y el tiempo en el que la pelota está volando sobre el suelo, use las siguientes fórmulas:
θ: ángulo = 45 °
vo: velocidad inicial
g: constante gravitacional = 9.8m / s ^ 2
x_max: distancia máxima = 180 m
t_max: tiempo máximo
reemplazando los valores de los parámetros y haciendo el tema de la primera fórmula que obtiene:
con este valor de vo usted calcula el tiempo máximo:
por lo tanto, la velocidad inicial de la pelota es de 42 m / sy el tiempo en que la pelota está en el aire es de 6.06 s
Which is the correct scientific notation of the number 0.000681?
Answer:
6.81 x 10^-4
Explanation:
Is the formular of preasure P=F÷A
Answer:
yes the formula of pressure is P = F/A
Answer:
yes it is
Explanation:
A body 'X' of weight 400N placed on the left side of a seesaw 250cm away from the pivot. A body 'Y' of weight 300N is placed on right side of seesaw 3.5m away from pivot. Has the seesaw attained equilibrium?Show your work?
Answer:
No.
Explanation:
if it's in equilibrium then the torque or moment of inertia on both sides should cancel.
Torque is a vector quantity, force times distance.
When doing these, make sure your units are the same by changing centimeters to meters first.
Left side is 400N * (-2.5m) = -1000 Nm
Right side is 300N * (3.5m) = 1050 Nm
-1000 Nm + 1050 Nm does not equal zero so there's a torque on the teeter and it will rotate clockwise. The system is not yet in equilibrium.
What is the gravitational force between Saturn and it’s moon
Answer:
The gravitational force between Saturn and it's moon is 1.62 m/s ^2
Explanation:
google it
Answer:
Explanation:
C bro
Can someone give me a detailed explanation on the physics of drums? How do drums get that sound from a physics perspective? (It is for a project on the physics of musical instrument and I have drums
Hi!
Explanation:
A set of wires (called snares) is stretched across a drum head at the bottom of the drum. The vibration of the bottom drum head against the snares produces the drum's characteristic "cracking" tone. Claps, snares, and other "sharp" or "bright" sounds are often used in similar ways in drum patterns.
The skin of the drum vibrates and makes the confetti dance. As the air molecules vibrate against each other, sound waves are formed and the sound of the drums can be heard. Fran explains that the pitch of a drum depends on how tight its skin is. ... Hit a drum hard and this makes big vibrations and a loud sound.
What is the magnitude of the magnetic field created 4.0m away from a 10.0 A current?
Answer:
The magnitude of the magnetic field created is 5 x 10⁻⁷ T
Explanation:
Given;
magnitude of current, I = 10.0 A
distance of the magnetic field, r = 4.0m
Apply Biot-Savart Law to determine the magnitude of of the magnetic field created;
[tex]B = \frac{\mu_oI}{2 \pi r}[/tex]
where;
B is the magnitude of of the magnetic field
μ₀ is constant
I is current
r is the distance of the field
[tex]B = \frac{4 \pi*10^{-7} *10}{2 \pi*4} = 5*10^{-7} \ T[/tex]
Therefore, the magnitude of the magnetic field created is 5 x 10⁻⁷ T