Answer:
20
Explanation:
20m= 1 seconds
40m= 2 seconds
180÷9=20
If an automobile slows from 26 m/s to 18 m/s in a period of 4.0 s, what was the average acceleration?
Answer: -2m/s²
Explanation:
Each second, the acceleration decreases of 2m/s²
N.B.: in physics, deceleration is also acceleration.
Can an object have positive acceleration and decreasing speed?.
A mass 25kg is attached to a spring which is held stretched a distance 120 cm by a force F=300N (Fig. 7-28), and then released. The spring compresses, pulling the mass. Assuming there is no friction, determine the speed of the mass m when the spring returns: (a) to its normal length (x = 0). (b)find the spring constant k?
Explanation:
Spring is stretched by force f to distance
"X"
now here by force balance we can say
f = kx
k = !
now here we will we say that energy stored in the spring will convert into kinetic energy
kx² = mv²
(x² = mv²
now solving above equation we will have
PART 2)
now for half of the extension again we can use energy conservation
ka²-k(x/2)² = 1 {mv²
¾fx=mv²
now the speed is given as
3 fr 4m V=
please help me solve all of them ( a, b, c and d ) thankiew !!
I’m also kind of in a rush
Answer:
a-
V= IR
9V = I ×( 12+6)
I = 9/ 18 A = 0.5 A
b
V=IR
240 = 6 A ×( 20 + R)
40 = 20 + R
R = 20 ohm
c
resultant resistance of the 2 parallel resistances= Ro
1/Ro = 1/ 5 + 1/ 20
1/Ro =( 20+5)/100
= 1/Ro = 1/4
Ro= 4 ohm
V=IR
V = 2A × ( 1+ 4 OHM)
V = 10V
d
equivalent resistance = Ro
1/Ro = 1/(2+8) + 1/(5+5)
1/Ro = 1/10 +1/10
2/10 = 1/ Ro
Ro= 10/2 = 5 ohm
V = IR
12V = I × 5Ohm
I=2.4 A
Help me quickly! please!!!
A cable pulls a car up a mountain with a force of 4 × 103 N at a vertical constant velocity of 5 m.s-1. It takes 5 minutes to reach the top.
(a)How much work is done in getting the car to the top?
(b)How much work would have been done if the vertical speed was 2,5 m.s-1?
(c)Calculate the power exerted on the cable car in those 5 minutes.
Answer:
(a) 6,000,000J
(b) 3,000,000J
(c) For A 20,000W
But for B 10,000W
The work done in getting the car to the top is equal to 6 ×10⁶ J. If the vertical speed is 2.5 m/s then, the work done will be 3 ×10⁶ J. The power exerted on the car is in 5 minutes is 20000 J/s.
What is work done ?In physics, work done is the dot product of force and displacement. Let w be the work done and F and ds be the force and displacement. Then
W = F.ds
It is given that the, the force of the cable is 4 × 10³ N. The velocity is 5 m/s and time is 5 minutes or 300 seconds. Now, the displacement is the product of time and velocity.
ds = velocity × time
= 300 s × 5 m/s
= 1500 m.
Thus the work done = F × ds
= 4 × 10³ N × 1500 m
= 6 ×10⁶ J .
If the velocity is reduced to half 2.5 m/s , then work done will be reduced to half as 3 ×10⁶ J.
Power is the rate of work done. Thus it is the ratio of work done to time. The power exerted on the car in 5 minutes = 6 ×10⁶ J /300s
= 20000 J/s
Hence, the power exerted on the cable car in 5 minutes is 20000 J/s.
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the definition of convetion
PLEASE ANSWER NEED HELP!!!!!!!! PLEASE THE CORRECT ANSWER!!!!!!
Jinan has high cholesterol and wants to do what he can to improve it through his diet. What would be the BEST thing for him to increase in his diet to address this issue?
A.
sugars
B.
protein
C.
carbohydrates
D.
unsaturated fat
PLEASE NO LINKS
Answer:
D. unsaturated fat
Explanation:
Unsaturated fats are considered the healthiest fats because they improve cholesterol, help reduce inflammation (a risk factor for heart disease), and help decrease the overall risk of developing heart disease. The main source of unsaturated fats are plant-based foods.
Answer:unsaturated fat
Explanation:
c. How can you explain natural selection in evolution of insects from the time they evolved till our days now?
A box with a weight of 20 newtons rest at a bottom of a ramp and is pushed to the end of the ramp with a force of 40 newtons. This ramp is an incline of 15 meters long. What is the maximum height of the ramp.
To move maximum height the friction force can be assumed to be
negligible.
The height of the ramp is 15 metersReasons:
The component of the weight acting on the incline, w = m·g·sin(θ)
Length of the ramp = 15 m
Potential energy of the box = 15 × sin(θ) ×20 = 300·sin(θ)
F × 15 = 300·sin(θ)
F = 20·sin(θ)
Work done by net force = Potential energy gained by the box
Work done by net force = (40 - 20·sin(θ)) × 15 = 300·sin(θ)
40 = 20·sin(θ) + 20·sin(θ) = 40·sin(θ)
sin(θ) = 1
θ = arcsin(1) = 90°
The ramp is at an inclination of 90°, therefore, the ramp is oriented vertically
The height of the ramp = The length of the ramp = 15 m
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Compare the amplitude of these waves.
help?
Answer:
The greater the amplitude of a wave then the more energy it is carrying.
Explanation:
E is carrying the most energy which means that it has the highest amplitude
A has the least energy because it has the lowest amplitude
a car is moving due south for 4hr and covered a distance of 144km what is the velocity of the car?
Answer:
velocity ,V=?,T=4hr,Distance ,144km,
V=distance divide by time
=144/4=36km/hr
solar power generates electricity from what source
an electric generator has an 18-cm-diameter, 120-turn coil that rotates at 60 hz in a uniform magnetic field that is perpendicular to the rotation axis.
The magnetic field strength is needed to generate a peak voltage 0.15 T.
The given parameters;
diameter of the coil, d = 18 cmradius of the coil, r = 9 cmnumber of turns, N = 120 turnsfrequency, f = 60 HzPeak voltage, E = 170 VThe area of the coil is calculated as follows;
[tex]A = \pi r^2\\\\A = \pi \times 0.09^2\\\\A = 0.0255 \ m^2[/tex]
The maximum emf induced in the coil is calculated as follows;
[tex]E_{max} = NBA \omega \\\\B = \frac{E_{max}}{NA\omega } \\\\[/tex]
where;
B is the magnetic field strengthω is the angular frequency = 2πf[tex]B = \frac{170 }{120 \times 0.025 \times 2\pi \times 60 } \\\\B = 0.15 \ T[/tex]
Thus, the magnetic field strength is needed to generate a peak voltage 0.15 T.
"Your question is not complete, it seems to be missing the following information";
An electric generator has an 18-cm-diameter, 120-turn coil that rotates at 60 hz in a uniform magnetic field that is perpendicular to the rotation axis.
What magnetic field strength is needed to generate a peak voltage of 170 V?
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2. All objects contain both what and what charges.
Answer:
All objects are composed of these atoms. ... Charged objects have an imbalance of charge - either more negative electrons than positive protons or vice versa. And neutral objects have a balance of charge - equal numbers of protons and electrons.
Explanation:
Explain why the 4th state of matter would and would NOT make an acceptable force field.
The 4th state of matter would make an acceptable force field.
The 4th state of matter which is plasma would make an acceptable force field because this fourth state of matter is present in ionized form which has two charges on it i.e. cation which is a positive charge and anion which is a negative charge.
We know that charges attract as well repel other objects if they are strong enough. Positive charge repel positive charge but attract negative charge so we can conclude that 4th state of matter would make an acceptable force field.
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Can anyone help me with this question? I’ll give BRAINLIEST to whoever answers first
Answer:
a) F = 84.64N
b) The force has to increase.
Explanation:
First of all, let's convert everything to the same unit system:
Vo = 0 m/s Vf = 98 mi/h * 1609.34 m / 1mi * 1h / 3600s = 43.8m/s
d = 1.7m m = 0.15kg
We can calculate force as:
F = m*a where a is the acceleration experiencd by the ball and m is its mass.
In order to calculate acceleration, we can use this formula:
Solving for a:
Now, the force will be:
F = m * a = 84.6N
As we can see in that previous equation, the force is directly proportional to the mass of the ball, so, assuming the final speed of the ball is the same as before (that is, the acceleration is the same), the force will increase in the same proportion as the mass does.
Each box weighs 10lb. The coefficient of static friction between box A and box B is 0.24, and the coefficient of static friction between box B and the inclined surface is 0.3. What is the largest angle for which box B will not slip
The largest angle for which box B will not slip is 16.7⁰.
The given parameters:
weight of box, W = 10 lbcoefficient of static friction between box A and box B, [tex]\mu_s_1[/tex] = 0.24coefficient of static friction between box B and the inclined surface, [tex]\mu_s_2[/tex] = 0.3The frictional force between box A and box B is calculated as;
[tex]F_f_1= \mu_s_1 (mg)[/tex]
The frictional force between box B and inclined surface is calculated as;
[tex]F_f = \mu_s_2 (2mg) cos(\theta)[/tex]
The net force on the boxes that results in no movement is calculated as;
[tex](2mg) sin(\theta) - F_f= 0\\\\(2mg) sin(\theta) = F_f\\\\(2mg) sin(\theta) = \ \mu_s_2 (2mg) cos(\theta)\\\\ sin(\theta) = \mu_s_2 cos(\theta)\\\\\mu_s_2 = \frac{sin(\theta)}{cos(\theta)} \\\\\mu_s_2 = tan(\theta)\\\\\theta = tan^{-1} (\mu_s_2)\\\\\theta = tan^{-1} (0.3)\\\\\theta = 16.7 \ ^ 0[/tex]
Thus, the largest angle for which box B will not slip is 16.7⁰.
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What is the frequency of light having a wavelength of 4. 50 x 10-6 cm.
The frequency of a photon of red light with wavelength 4.50 x 10−7m is 6.67 x 1014Hz.
What is a lol diagram.
Answer:
LOL Diagrams
a way to represent how the energy is stored in the chosen system during various snapshots and to represent any changes in total energy for the system. Each “L” represents how the energy is stored during a particular snapshot (instant). The “O” shows the objects inside and outside the system.
If anyone knows please anwser
Answer:
C.
Explanation:
Answer:
c. Radio and T.V. signals
2. A student becomes so excited by the whole idea of black holes that he decides to jump into one. It has a mass 10 times the mass of our Sun. What is the trip like for him
Answer:
*Disclaimer you can't actually do that, or at least not yet because the nearest black hole is at least 1,000 light years away. But if we could...
His journy would be pretty fast and horrific. For him, he would slowly be streched apart or spegetified into a string of atoms as he nears the event horizoin. But for an outside observer he would apear to go slower and slower and would never actualy reach the event horizion. This is becuase of einstines general relativity, massive objects slow time down. He would also apear to become red as the lights wavelength is streched out due to the entense gravity of the black hole.
What is one effect of the uneven heating of Earth caused by the Sun?
options:
Rotation of Earth
Generation of wind
Oceans losing salt
Plants failing to grow
Answer:
The uneven heating results in some of the atmosphere to be warmer than other parts and changes in volume and pressure which result in updrafts and can cause thunderstorms and other violent weather.
Explanation:
Generation of wind
Daniel is 50.0 meters away from a building. He observes that his line-of-sight to the tip of the building makes an angle of 63.0° with the horizontal. What is the height of the building?
Answer:
willie tower
Explanation:
mataas kasi
5 a
What causes the pressure of air at the Earth's surface?
Answer:
Atmospheric pressure is caused by the gravitational attraction of the planet on the atmospheric gases above the surface and is a function of the mass of the planet, the radius of the surface, and the amount and composition of the gases and their vertical distribution in the atmosphere
Explanation:
1. A race car accelerated from rest to 34.7 m/s by the time it crossed the finish line. The race car moved in a straight line and traveled from the starting line to the finish line in 7.81 seconds. What was the acceleration of the race car?
Answer: 4.44302176697 m/s^2
Explanation:
formula for acceleration is (final velocity - initial velocity)/time. So in your case:
(34.7m/s - 0m/s)/ 7.81s = 4.44302176697 m/s^2
plz help will mark brainliest
Explanation:
The rod can be in equilibrium only if the resultant force is 0 and the moment around any point of the rod must be equal to 0.
We have to take moments around the pivoted point.
Moment = Force × Perpendicular distance to the force
For the rod to be in equilibrium,
Clockwise moment - Anticlockwise moment = 0
Clockwise moment = Anticlockwise moment
The distance between pivoted point and the weight of rod = 50 cm - 30 cm = 20 cm
So 20 cm× 1.2 N produces a Clockwise moment
If Perpendicular distance between pivoted point and 2N load is x,
Anticlockwise moment = x × 2N
20 cm× 1.2N = 2N × x
x = 12 cm
So 2 N load is at 12 from the pivoted point.
From the left edge of the meter ruler, 2N load is at 30-12 cm distance
= 18 cm
Answer: 18 cm
Explanation:
what do u guys think of my drawing?
Answer: yess sirrrrrrrr
Explanation:
Answer:
oou I like it! u did a good job ^^
how fast should a girl 35kg Run so that her kinetic energy becomes 700 J?
find the impulse of a 20.0 KG object accelerates to8.1 M/S from 2.3 M/S
Answer:
116 N•s
Explanation:
change in momentum = mvf-mvi
= m(Vf - Vi)
= 20( 8.1-2.3)
change in momentum= 116 kg•m/s
: .impulse is 116 N•s
discrete packets of kinetic energy in light are called
Answer:
Photons
Explanation:
I just know
Discrete packets of kinetic energy in light are called photons. Photons are fundamental particles of light and electromagnetic radiation. The correct answer is photons.
Photons are fundamental particles of light and electromagnetic radiation. They carry energy in discrete quantities, known as quanta or packets, and exhibit both wave-like and particle-like properties.
The energy of a photon is directly proportional to its frequency, and inversely proportional to its wavelength. When light interacts with matter, it can transfer its energy to the particles it interacts with, leading to various phenomena such as absorption, reflection, and emission.
Therefore, Discrete packets of kinetic energy in light are called photons.
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