Answer:
If the velocity and acceleration are in the same direction (both have the same sign - both positive or both negative) the object is speeding up. If the velocity and acceleration are in opposite directions (they have opposite signs), the object is slowing down.
Please mark my answer brainliest for further answers :)Which material transmits the most visible light?
A.Sunglass lens
B.Mirror
C.Clear glass
D.Black cloth
Answer:
c
Explanation:
A 1,680 kg satellite is in a circular orbit around Earth with a tangential speed of 6,578 m/s. What is the height of the satellite above the surface of the Earth?
Answer:
Recall that Earth’s radius is 6.38 × 106 m and Earth’s mass is 5.97 × 1024 kg.
Explanation:
Answer:
A- 2.7 on USA Test prep
Explanation:
A spring of force constant 1500 Nm-l is acted
upon by a constant force of 75 N. Calculate
the potential energy stored in the spring.
Answer:
1.876 J
Explanation:
First, let’s calculate the compression of the spring from the Hooke’s law:
F=kx,
here, F=75 N is the force acted on the spring, k=1500 N⁄m is the force constant of the spring, x is the compression of the spring.
Then, we get:
x=F/k=(75 N)/(1500 N/m)=0.05 m.
Finally, we can find the potential energy stored in the spring:
PE=1/2 kx^2=1/2∙1500 N/m∙(0.05 m)^2=1.875 J.
correct my answer if it's wrong ^^
Define the types of friction and give FOUR examples of each
Static Friction
Rolling Friction
Sliding Friction
Fluid Friction
A plane is flying with an airspeed of 190 miles per hour and heading 150°. The wind currents are running at 30 miles per hour at 170° clockwise from due north. Use vectors to find the true course and ground speed of the plane. (Round your answers to the nearest ten for the speed and to the nearest whole number for the angle.)
Answer:
[tex]Vg=200mile/hr[/tex]
[tex]\theta=153 \textdegree[/tex]
Explanation:
From the question we are told that:
Plane airspeed [tex]v_p=190mil/h[/tex]
Plane direction [tex]\angle=150 \textdegree[/tex]
Wind current speed [tex]V_w=30mil/h[/tex]
Wind direction [tex]\angle=150 \textdegree[/tex]
Generally the vector form of the forces is mathematically given by
For plane
[tex]\angle Q_p=90-150 \textdegree[/tex]
[tex]V_p=170(cos60 \textdegree ,sin60 \textdegree)[/tex]
[tex]V_p=(85,-147.224)[/tex]
For wind
[tex]\angle Q_w=90-170 \textdegree[/tex]
[tex]V_w=30(cos-80 \textdegree ,sin-80 \textdegree)[/tex]
[tex]V_w=(5.2,-29.54)[/tex]
Generally the equation for resultant force is mathematically given by
[tex]v_r=V_a+V_w[/tex]
[tex]v_r=(85,-147.224)+(5.2,-29.54)[/tex]
[tex]v_r=(90.21,-176.76)[/tex]
[tex]v_r=198.45\angle -63[/tex]
Therefore ground speed
[tex]V_g=198.5miles/hr[/tex]
[tex]Vg=200mile/hr[/tex]
Direction
[tex]\theta=(90+63)=153 \textdegree[/tex]
[tex]\theta=153 \textdegree[/tex]
HELP ME ASAP PLZZZ!!!
In which reaction are the atoms of elements rearranged?
A truck with a mass of 15,000 kg moving at 25 m/s crashes into the back of a small 1,100 kg car moving at 15 m/s. They
stick together after the collision. Calculate the momentum of the system before the collision and after the collision.
Explanation:
Given that,
Mass of a truck = 15,000 kg
Speed of the truck = 25 m/s
Mass of car = 1,100 kg
Speed of the car = 15 m/s
As they stick together after the collision. Let V be the speed after the collision.
Initial momentum of the system,
[tex]P_i=15000\times25+1100\times15\\\\=391500\ kg-m/s[/tex]
Final momentum of the system,
[tex]P_f=(15000+1100)V\\\\=16100V[/tex]
Hence, this is the required solution.
If spring has a spring constant of 500 N/m and is stretched .50 meters,how much energy is stored in the spring ((show work for full credit, show equation))
Answer:
The energy stored is: 62.5 Joules
Explanation:
Given
[tex]k = 500N/m[/tex] --- spring constant
[tex]x = 0.5m[/tex] --- stretch
Required
The amount of energy
This is calculated as:
[tex]U = \frac{1}{2} kx^2[/tex]
[tex]U = \frac{1}{2} * 500N/m * (0.5m)^2[/tex]
[tex]U = 250N/m * (0.5m)^2[/tex]
[tex]U = 62.5\ J[/tex]
Please help please real quick
Answer:
1. (a) The final velocity is 20 m/s
(b) The distance travelled is20 meters
2. The distance travelled by the train in the 30 seconds is 825 meters
3. The most correct option is;
(d) 53 km
4. The heat, developed by the electric iron is 15,000 joules
5. a) In the first network the resistance between A and B is 2 Ω
b) In the second network the resistance between A and B is 4Ω
c) In the third network the resistance between A and B is 6Ω
d) In the fourth network the resistance between A and B is 2Ω
Explanation:
1. (a) The parameters of the cheetahs motion are;
The initial motion (velocity) of the cheetah = 0 m/s (The cheetah starts from rest)
The acceleration of the cheetah, a = 2 m/s²
The duration of the acceleration of the cheetah, t = 10 seconds
The kinematic equation of the motion of uniform acceleration, of the cheetah can be written in the following form;
v = u + a·t
s = u·t + 1/2·a·t²
Where;
v = The final velocity
u = The initial velocity = 0 m/s
a = The acceleration of the cheetah = 2 m/s²
s = The distance traveled
∴ v = 0 + 2 × 10 = 20
The final velocity, v = 20 m/s
(b) From s = u·t + 1/2·a·t², we have;
s = 0 × 10 + 1/2 × 10 × 2² = 20
The distance travelled, s = 20 meters
2. The given details of the motion of the train are;
The initial velocity of the train, u = 20 m·s⁻¹
The acceleration of the train, a = 0.5 m·s⁻²
The duration of the train's acceleration, t = 30 seconds
Therefore, the distance travelled, 's', is given by; s = u·t + 1/2·a·t²
∴ s = 20 × 30 + (1/2) × 0.5 × 30² = 825
The distance travelled by the train in the 30 seconds, s = 825 meters
3. The given distance the truck covers with the average speed of 80 km/h, d₁ = 40 km
The distance the truck then covers with the average speed of 40 km/h, d₂ = 40 km
[tex]Average \ speed = \dfrac{Total \ distance}{Time}[/tex]
[tex]\therefore time, \, t = \dfrac{Total \ distance}{Average \ speed}[/tex]
The time it takes the truck to cover the 40 km at 80 km/h = 40 km/(80 km·h) t₁ = 0.5 hour
The time it takes the truck to cover the 40 km at 80 km/h = 40 km/(40 km·h) t₂ = 1 hour
The total time taken to cover both 40 km distances, t = t₁ + t₂
∴ The total time taken to cover both 40 km distances, t = (0.5 + 1) hour = 1.5 hours
The total distance covered at both speeds, d = d₁ + d₂
∴ d = 40 km + 40 km = 80 km
The average speed of the truck for the total distance, [tex]v_{average}[/tex] = d/t
∴ [tex]v_{average}[/tex] = 80 km/1.5 hours = 53.[tex]\overline 3[/tex] km/h ≈ 53 km/h
The average speed of the truck for the total distance, [tex]v_{average}[/tex] ≈ 53 km/h
The correct option is (d) 53 km
4. The heat, 'H', developed by the electric iron is given by the following formula;
H = I²·R·t
Where;
I = The current flowing in the electric iron = 5 A
R = The resistance of the iron = 20Ω
t = The time duration of the flow of the current = 30 s
∴ H = (5 A)² × 20 Ω × 30 s = 15,000 joules
The heat, developed by the electric iron, H = 15,000 joules
5. Let 'R' represent the resistance between A and B in each network
a) For the first network, we have;
1/R = 1/(2 + 2) + 1/(2 + 2) = 1/4 + 1/4 = 1/2
∴ R = 2 Ω
∴ The resistance between A and B is 2 Ω
b) For the second network, we have;
R = 1/(1/2 + 1/2) + 3 = 4
R = 4Ω
∴ The resistance between A and B is 4 Ω
c) For the third network, we have;
R = 2 + 1/(1/4 + 1/4) + 2 = 6
R = 6Ω
∴ The resistance between A and B is 6 Ω
d) For the fourth network, we have;
R = 1/(1/2 + 1/2) + 1/(1/2 + 1/2) = 2
R = 2Ω
∴ The resistance between A and B is 2 Ω
1. The movement of water between the oceans, atmosphere, land, and living things is the ______________________.
2. The changing of water from liquid to vapor is called ______________________.
3. During ______________________, water vapor cools and returns to a liquid state.
4. Water that falls from the atmosphere to the land and oceans is called ______________________.
5. Precipitation that falls on land and then flows into streams, rivers, and lakes is called ______________________.
6. Precipitation that seeps into the ground and is stored among rocks is called ______________________.
7. Water vapor is released by plants and returned to the environment in a process called ______________________.
8. Name three reasons water is needed for life on Earth.
Is telekinesis real??? I really wanna start learning it!
Answer:
Highly doubt something that requires great focus and mental strength exists
A longitudinal wave is a type of wave that transfers energy
Answer:
It transfers energy parallel to the direction of wave motion. A transverse wave..
Explanation:
Answer:
The answer is a Wave Motion
Explanation:
A longitudinal wave is a type of wave that transfers energy is called," Wave Motion".
Hope you have a great day :)
m/s2
Which equation links acceleration, mass and resultant force?
(d)
Tick one box.
resultant force = mass + acceleration
resultant force = mass x acceleration
resultant force = mass - acceleration
resultant force = mass : acceleration
oric Soko
Answer:
resultant force = mass × acceleration
Answer:
Resultant netforce= mass x acceleration
Explanation:
Fnet is directly proportional to acceleration, and inversly proportinal to mass.
According to the graph, at which time during a sunny summer day are the
particles in a swimming pool likely to be moving the most quickly?
A. 6:00 p.m.
B. 11:00 p.m.
C. 5:00 a.m.
D. 8:00 a.m.
Answer: A 6:00 pm
Explanation: took the exam
PLEASE HELP!! I PROMISE I'LL GIVE BRAINLIEST!!
What would your life look like if you had to use only analog signals?
like a black cloud
Explanation:
Define: Signals
Before going too much further, we should talk a bit about what a signal actually is, electronic signals specifically (as opposed to traffic signals, albums by the ultimate power-trio, or a general means for communication). When one speaks of analog one often means an electrical context, however mechanical, pneumatic, hydraulic, and other systems may also convey analog signals.
An analog signal uses some property of the medium to convey the signal's information. Any information may be conveyed by an analog signal, often such a signal is a measured change in physical phenomena, such as sound, light, temperature, position, or pressure.
For example, in sound recording, changes in air pressure (that is to say, sound) strike the diaphragm of a microphone which causes related changes in a voltage or the current in an electric circuit. The voltage or the current is said to be an "analog" of the sound.
A 2018 Tesla Model S has a horsepower of 518. How many watts of power does this car model have?
Answer:
It depends on the model but these are the watts of each motor
Explanation:
Un motor: 258 HP (262 CV) Dual motor: 154 kW (209 CV) y 197 kW (268 CV). Performance: 154 kW (209 CV) y 225 kW (306 CV).
What do you call the shot that starts on the right side and continues through to the left
side for a right handed player?
Answer:
When a right-handed golfer’s tee shot curves to far to the left, the shot is described as a “hook.” This shot typically occurs when the club head moves across the ball from left to right, imparting side-spin on the ball
PLEASE HELP ME I AM TIMED!
Answer:
Well my good friend the other person did not give U a good answer, it is actually the third one
Explanation: well it is the most logical of all the answers if you think about it and a lot of the creatures we have in the water today are thought of to have once lived on land based on the fossils we still find to this very day my friend
Static electricity is an excess of charge.
A. True
B. False
Answer:
Its true
Explanation:
SE UM CORPO ELETRICAMENTE NEUTRO É CARREGADO COM PROTONS, entao afirmamos; a) fica carregado negativamente b) fica carregado só com cargas positivas c) fica carregado positivamente d) fica com excesso de eletrons e) continua eletricamente neutro
Answer:
c) It gets positively charged
Explanation:
If an electrically neutral body is loaded with protons so it gets positively charged because proton has positive charge. When the protons is added to the neutral body, it can't remain neutral because the quantity of positive charges increases in the nucleus and it gets positively charged while on the other hand, the atom from which protons are taken will acquire negative charge due to presence of more number of electrons and we know that electrons has negative charge.
Cold water flows to the solar panels at 15°C. During the day, the panels supply 3.8 kg of hot water
at 65°C every hour.
(a) Calculate the average energy that the solar panels deliver to the water in one hour.
Specific heat capacity of water = 4200 J/(kg°C).
Answer:
The average energy that the solar panel delivers to the water in one hour is 798,000 Joules
Explanation:
The given parameters are;
The temperature of the water that flows to the solar panels, T₁ = 15°
The mass of the hot water the panel supplies during the day, m = 3.5 kg
The temperature of the hot water supplied by the panel, T₂ = 65 °C
The heat capacity of the water, c = 4,200 J/(kg·°C)
The heat delivered to the solar panels in one hour, ΔQ, is given by the following formula
ΔQ = m·c·ΔT
m = 3.8 kg, c = 4,200 J/(kg·°C), and ΔT = T₂ - T₁ = 65 °C - 15 °C = 50 °C
∴ ΔQ = 3.8 kg × 4,200 J/(kg·°C) × 50°C = 798,000 joules
∴ΔQ = 798,000 joules
The average energy that the solar panel delivers to the water in one hour, ΔQ = 798,000 joules.
A car drives for 50 seconds and travels 2 meters what is its velocity
Speed = (distance) / (time)
Speed = (2 m) / (50 s)
Speed = 0.04 m/s
There's not enough information to state the car's velocity. We don't know anything about the direction it moved.
Energy cannot be created nor destroyed. A. Ella said "a lot of energy in the hot water has disappeared." Explain why her statement is wrong?
Answer:
See Explanation
Explanation:
The principle of conservation of energy states that; energy can neither be created nor destroyed but is converted from one form to another.
In view of this principle, Ella can not be correct when she says that a lot of energy has disappeared. The use of the term "disappeared" connotes the idea that the energy no longer exists which does not happen.
Hence, energy can not "disappear" from hot water rather the energy in the water may be transferred to the surroundings.
PLEASE HELP!!!!!!!!!!!!!!!!Match the label with the reason it might be important to the consumers.
1. country of origin
Kelli only buys vegetables grown
without pesticides.
Angie only buys foods made with
2. Organic Certification
sea salt to cut sodium intake.
3. dietary guideline
Nikki prefers to buy local products
to lessen her carbon footprint.
Answer:
1 is Nikki
2 is Kelli
3 is Angie
Explanation:
Hope this helps!
why don't planets crash into each other?
Answer:Planets can't be in just any orbit, they have to be far enough apart so that they don't hit each other, and aren't drawn into collision by gravity
Explanation:
9.) This 200 kg
stag that weighs
1,960 N on earth
would only weigh
324 N on the
moon. Calculate the moon's
acceleration due to gravity.
Answer:
Mass on moon = 33.06 kg
Explanation:
Given the following data;
Mass on earth = 200 kg
Weight on earth = 1960 N
Weight on moon = 324 N
To find the mass on moon;
First of all, we would determine the acceleration due to gravity.
Weight = mass * acceleration due to gravity
1960 = 200 * g
g = 1960/200
g = 9.8 m/s²
Next, we find the mass on moon;
Mass on moon = weight on moon/acceleration due to gravity
Mass on moon = 324/9.8
Mass on moon = 33.06 kg
A 100-watt lightbulb uses 1 kilowatt-hour of electrical
energy when it is on for ten hours. How much energy does
a 25-watt lightbulb use when it is on for ten hours?
Answer:
Energy = 0.25 kilowatt-hour
Explanation:
Given the following data;
Power = 25 Watts
Time = 10 hours
Power can be defined as the energy required to do work per unit time.
Mathematically, it is given by the formula;
[tex] Power = \frac {Energy}{time} [/tex]
To find the energy consumed;
Energy = power * time
Substituting into the formula, we have;
Energy = 25 * 10
Energy = 250 Watt-hour
To convert to kilowatt-hour, we would divide by 1000;
Energy = 250/1000
Energy = 0.25 kilowatt-hour
A machine raised a load of 360N through a distance of 0.2m. The effort, a force of 50N moved 1.8m during the process. Calculate the efficiency of the machine.
Select one:
a. 40%
b. 100%
c. 80%
d. 60%
Answer:
c. 80%
Explanation:
Given;
load raised by the machine, L = 360 N
distance through which the load was raised, d = 0.2 m
effort applied, E = 50 N
distance moved by the effort, e = 1.8 m
The efficiency of the machine is calculated as follows;
[tex]Efficiency = \frac{ 0utput \ work }{1nput \ work} \times 100\% \\\\Efficiency = \frac{Load \ \times \ distance \ moved \ by \ load }{Efort \ \times \ distance \ moved \ by \ effort} \times 100\%\\\\Efficiency = \frac{360 \times 0.2}{50 \times 1.8} \times 100\%\\\\Efficiency =80\%[/tex]
Therefore, the efficiency of the machine is 80%
A proton travels through uniform magnetic and electric fields. The magnetic field is in the negative x direction and has a magnitude of 2.48 mT. At one instant the velocity of the proton is in the positive y direction and has a magnitude of 1840 m/s. At that instant, what is the magnitude of the net force acting on the proton if the electric field is (a) in the positive z direction and has a magnitude of 5.19 V/m, (b) in the negative z direction and has a magnitude of 5.19 V/m, and (c) in the positive x direction and has a magnitude of 5.19 V/m
Answer:
a) F = 15.6 10⁻¹⁹ k^ N, b) F = -1 10⁻¹⁹ k^ N,
c) F = (8.3 i^ + 73 k^) 10⁻¹⁹ N
Explanation:
In this exercise we calculate the magnetic and electric force separately.
Let's start by calculating the magnetic force
F_m = q v x B
where bold letters indicate vectors, the modulus of this expression is
F_m = q v B
the direction is given by the right hand rule, where the thumb points in the direction of velocity, the fingers are extended in the direction of the magnetic field and the palm is in the directional ne force if the charge is positive
let's calculate the magnitude
F_m = 1.6 10⁻¹⁹ 1840 2.48 10⁻³
F_m = 7.3 10⁻¹⁹ N
we calculate the direction, the thumb is in the direction of + y,
fingers extended in the direction of -ax
the palm remains + z
therefore the magnetic force is in the direction of the positive side of the z axis
The electric force is
F_e = q E
give several possibilities for the electric field
a) electric field E = 5.19 V / m in the direction of + z
we calculate
F_e = 1.6 10⁻¹⁹ 5.19
F_e = 8.3 10⁻¹⁹ N
the total force is
F = F_m + F_e
F = (8.3 k ^ + 7.3 k ^) 10⁻¹⁹
F = 15.6 10⁻¹⁹ k^ N
b) in the -z direction
F_e = -8.3 10⁻¹⁹ k^ N
F = Fm + Fe
F = (-8.3 k ^ + 7.3 k ^) 10⁻¹⁹
F = -1 10⁻¹⁹ k^ N
c) in the + x direction
F_e = 8.3 10⁻¹⁹ i^ N
the total force is
F = (8.3 i^ + 73 k^) 10⁻¹⁹ N
10. A pitcher in a professional baseball game throws a fastball, giving the baseball
a momentum of 5.83 kg. m/s. Given that the baseball has a mass of 0.145 kg,
what is its speed?
Answer: 40.2m/sec
Work: v=p/m= 5.83kg/0.145k=40.2cm/sec