a man walks 15 meters in 15 seconds. what is his speed
Answer:
1 meter per second
Explanation:
Every second, he walks 1 meter because 15 ÷ 15 = 1
Choose forces from the box to complete these sentences.
Answer:Upthrust, Weight
Explanation:
The upward force is called Upthrust.
The downward force is called weight.
Whenever a body is submerged fully or partially in the liquid, it experiences an upward force that is equal to the weight of water replaced.
Light waves are
A.rotating waves.
B.longitudinal waves.
C.circular waves.
D.transverse waves
SHOCKING
Explanation:
Answer:
D i promises.
Explanation:
light waves can go 2 direction
Which of the following skills that you learn while participating in a team sport is also a life skill that employers look for?
A.
Showing respect to others
B. Working well with others
c.
Problem solving
D
All of the above
Answer:
The answer is all of the above
Explanation:
Answer:
D
Explanation:
How much force does it take to accelerate a 3.50 kg mass from 3.00 m/s to 17.0 m/s in a time of 2.00 seconds?
Answer:
Force = 24.5 Newton
Explanation:
Given the following data;
Mass = 3.50 kg
Initial velocity, u = 3 m/s
Final velocity, v = 17 m/s
Time, t = 2 seconds
To find the force;
First of all, we would determine the acceleration of the object using the formula;
Acceleration = (v - u)/t
Acceleration = (17 - 3)/2
Acceleration = 14/2
Acceleration = 7 m/s²
Now, we can find the force using the formula;
Force = mass * acceleration
Force = 3.5 * 7
Force = 24.5 Newton
A student of mass 45kg, who is undergoing National Service training, takes 6s to climb a flight of stairs that had 36 steps. If each step is 16cm high, what is the power of the student?
Answer:
Approximately [tex]4.2 \times 10^{2}\; \rm W[/tex] on average in the vertical direction (assuming that [tex]g = 9.8\; \rm N \cdot kg^{-1}[/tex].)
Explanation:
Vertical displacement of this student in [tex]6\; \rm s[/tex]: [tex]36 \times 16\; \rm cm = 36 \times (0.16\; \rm m) = 5.76\; \rm m[/tex].
Average vertical velocity of this student: [tex]v = \displaystyle \frac{5.76\; \rm m}{6\; \rm s} = 0.96\; \rm m \cdot s^{-1}[/tex].
The average vertical force that this student exerts on the ground would be equal to the weight of this student:
[tex]F = W = m \cdot g = 45\; \rm kg \times 9.8\; \rm N \cdot kg^{-1} = 441\; \rm N[/tex].
The average power of this student in the vertical direction is equal to the product of the force and velocity of this student in that direction:
[tex]P = F \cdot v = 441\; \rm N \times 0.96\; \rm m \cdot s^{-1} \approx 4.2\times 10^{2}\; \rm W[/tex].
____ 2. When an object is heated to the point that it glows, the process is called incandescence. ____________________
Answer:
True
Explanation:
Incandescence material are those which glow on being heated above a particular point. For example an incandescence bulb which has a filament. when the filament is heated it starts to glow.
The least energy efficient type of electronic lights typically used in residential buildings are usually called incandescent lamps. Although ineffective, incandescent lamps provide a variety of important advantages, they are inexpensive to purchase, turn on instantly and are available in a wide range of sizes and shapes.
A 10,000-watt radio station transmits at 535 kHz.
Calculate the energy of a single photon at the transmitted frequency.
A)3.55 × 10-28 J/photon
B)3.55 × 10-31 J/photon
C)6.63 × 10-30 J/photon
The energy of a single photon at the transmitted frequency is
A)3.55 × 10^(-28)J/photon
What is the energy of a single photon?Energy of photon can be rewritten as
E=hv,
Where, h is planck's constant
λ is the wavelength of photon
Where f is the frequency of photon
Thus, the energy of a single photon at the transmitted frequency obtained by using the formula, Energy (E) is equal to Planck's constant (h) times the frequency.
E=6.63×10^(-34)× 535×10^3
E =3.55 × 10^(-28) (J)
Photon energy doesn't depend on the power of radio station
Learn more about the Energy here;
https://brainly.com/question/3838760
#SPJ2
Air from a metal can is removed so the pressure in the can decreases to 70000Pa, the can is then sealed. The pressure from outside the can is atmospheric pressure which is 100kPa. The area of one side of the can is 1.5m2, find the resultant force on this side of the can.
Answer:
F = 45 KN = 45000 N
Explanation:
Considering the downward direction as the positive direction:
[tex]P = P_1 - P_2[/tex]
where,
P = Resultant Pressure = ?
P₁ = Atmospheric Pressure = 100 KPa
P₂ = Pressure inside the can = 70000 Pa = 70 KPa
Therefore,
[tex]P = 100\ KPa - 70\ KPa\\P = 30\ KPa[/tex]
Now the resultant force will be given as:
[tex]F = PA[/tex]
where,
F = resultant force = ?
A = Area of side of can = 1.5 m²
Therefore,
[tex]F = (30\ KPa)(1.5\ m^2)\\[/tex]
F = 45 KN
A young boy swings a yo-yo horizontally above his head so that the yo-yo has a centripetal acceleration of 200 m/s^2. If the yo-up’s string is 0.33 m long, what is the yo-up’s tangential speed?
Answer:
v = 8.12 m/s
Explanation:
The centripetal acceleration of the yo-yo is given by the following formula:
[tex]a_c = \frac{v^2}{r}\\\\v^2 = a_cr\\v = \sqrt{a_cr}[/tex]
where,
v = tangential speed = ?
ac = centripetal acceleration = 200 m/s²
r = radius = length of string = 0.33 m
Therefore, using the given values in the formula, we get:
[tex]v = \sqrt{(200\ m/^2)(0.33\ m)}[/tex]
v = 8.12 m/s
The Doppler Effect is caused by which of the following?
Select all that apply…
A - motion of the source
B - the type of wave
C - original frequency of the source
D - motion of the observer
E - type of medium the wave is in
Answer:
the type of wave
Explanation:
Description: Doppler Effect works on both light and sound objects. For instance, when a sound object moves towards you, the frequency of the sound waves increases, leading to a higher pitch. Conversely, if it moves away from you, the frequency of the sound waves decreases and the pitch comes down.
Question 5 of 10
What are two things that happen when a home computer scanner uses
electromagnetic waves?
A. Red light shines on patterns of black and white, recording the
pattern of reflected light.
B. Objects are exposed to X-rays, which either pass through or are
absorbed by the objects.
C. A silicon chip releases electrons by the photoelectric effect,
producing an image.
D. A charge-coupled device captures visible light that is reflected off
an object
Answer: B. Objects are exposed to X-rays, which either pass through or are
absorbed by the objects.
C. A silicon chip releases electrons by the photoelectric effect,
producing an image.
Explanation:
When a magnetic field is first turned on, the flux through a 20-turn loop varies with time according to Φm=5.0t2−2.0t, where Φm is in milliwebers, t is in seconds, and the loop is in the plane of the page with the unit normal pointing outward. (a) What is the emf induced in the loop as a function of time? What is the direction of the induced current at (b) t = 0, (c) 0.10, (d) 1.0, and (e) 2.0 s?
Answer:
A) ( - 200t + 40 ) volts
B) b) anticlockwise , c) anticlockwise , d) clockwise , e) clockwise
Explanation:
Given data:
magnetic flux (Φm) = 5.0t^2 − 2.0t
number of turns = 20
a) determine induced emf
E = - N [tex]\frac{d\beta }{dt}[/tex]
= - N ( 10t - 2 ) = - 20 ( 10t - 2 )
= - 200t + 40 volts
b) Determine direction of induced current
i) at t = 0
E = - 0 + 40 ( anticlockwise direction )
ii) at t = 0.10
E = -20 + 40 = 20 ( anticlockwise direction )
iii) at t = 1
E = - 200 + 40 = - 160 ( clockwise direction)
iv) at t = 2
E = -400 + 40 = - 360 ( clockwise direction )
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
A wave has a frequency of 60 Hz and a wavelength of 1.7 meters. What is the speed of this wave? equation, substitution
Answer:
v = 102 m/s
Explanation:
Given that,
The frequency of a wave, f = 60 Hz
Wavelength = 1.7 m
We need to find the speed of this wave. The formula for the speed of a wave is given by
[tex]v=f\lambda[/tex]
Substitute all the values,
[tex]v=60\times 1.7\\\\v=102\ m/s[/tex]
So, the speed of the wave is equal to 102 m/s.
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.
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).
when a metal reacts with a non-metal it forms what???
Answer:
When metals react with non-metals, electrons are transferred from the metal atoms to the non-metal atoms, forming ions. The resulting compound is called an ionic compound.
:
p me have no brain please help I just wanna get through the year
According to the law of conservation of mass, what is the mass of sodium oxide (Na20) formed in this reaction? 4Na 91.96 g 02 32.00 g 2Na 0 ?
A. 247.92 grams
B. 123.96 grams
C. 61.68 grams
D. 495.84 grams
Answer:
B. 123.96 grams
Explanation:
A 2.5m long steel piano wire has a diameter of 0.5cm how great is the tention in the wire if it stretches by 0.45cm when tightened taking the young's modulus to be 2.0×10^11 N/m^2
Answer: Their u go i found it their was about 3 pages i did not no what pages u had to do.
Explanation:
A 2.0 kg sphere with a velocity of 6.0 m/s collides head-on and elastically with a stationary 10 kg sphere
Question: A 2.0 kg sphere with a velocity of 6.0 m/s collides head-on and elastically with a stationary 10 kg sphere, What is thier velocities after collision.
Answer:
v = 6 m/s, v' = 0 m/s
Explanation:
From the question,
For Elastic collision,
mu+m'u' = mv+m'v'......................... Equation 1
Where m = mass of the first sphere, m' = mass of the second sphere, u = initial velocity of the first sphere, u' = initial velocity of the second sphere, v = final veolocity of the first sphere, v' = final velocity of the second sphere.
Also,
The relative velocity before collision = relative velocity after collision
u-u' = v-v'............................ Equation 2
Given: m = 2 kg, m' = 10 kg, u = 6 m/s, u' = 0 m/s
Substitute into equation 1 and 2
2(6)+10(0) = 2v+10v'
2v+10v' = 12.............. Equation 3
6-0 = v-v'
v-v' = 6 ................... Equation 4
Solve equation 3 and 4 simultaneously.
v = 6+v'............. Equation 5
Substitute equation 5 into equation 3
2(6+v')+10v' = 12
12+2v'+10v' = 12
12v' = 12-12
v' = 0/12
v' = 0 m/s.
Also substitute the value of v' into equation 5
v = 6+0
v = 6 m/s
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.
Two resistors, 2.50 Ω and 4.95 Ω, are wired in series to a 12.00 V battery. What is the equivalent resistance of the circuit?
Answer:
7.45 Ω
Explanation:
From the question given above, the following data were obtained:
Resistor 1 (R₁) = 2.50 Ω
Resistor 2 (R₂) = 4.95 Ω
Voltage (V) = 12 V
Equivalent Resistance (Rₑq) =?
Since the resistors are in series arrangement, the equivalent resistance can be obtained as follow:
Rₑq = R₁ + R₂
Rₑq = 2.5 + 4.95
Rₑq = 7.45 Ω
Therefore, the equivalent resistance is 7.45 Ω
Factors that affect the rate at which candle wax melts
Answer:
There are several factors such as candle size, wax type, additives etc. that affect the rate of melting of candle
Explanation:
Following factors affect the rate at which the candle wax melts -
a) Candle size
b) Temperature of the surrounding environment
c) Type of wax used
d) Additives in the candle
e) Chemical structure of the wax
State two advantages of thermal expansion
Higher Power Efficiency and Eliminates Risk of Compressor Breakdown
Hurryyyyy pleaseeeee!!!!!
An ideal gas triples in volume in an adiabatic process. the initial pressure is 1.4 x 10^5 Pa. what is the final pressure? let y = 1.67.
5.8 x 10^4 Pa
2.2 x 10^4 Pa
1.4 x 10^4 Pa
1.0 x 10^5 Pa
Answer: 2.2x10^4
Explanation: in a adiabatic process pV^y = constant.
So V2=3V1 and p2 = p1 / 3^1.67 = 2.2x10^4 Pa
Two moving objects have the same momentum. Object 1 has three times the mass of Object 2; therefore, Object 1 has:
the same the velocity of Object 2
three times the velocity of Object 2
nine times the velocity of Object 2
one-third the velocity of Object 2
one-ninth the velocity of Object 2
ANSWER
0ne third the velocity of object 2
Explanation:
P1=P2
m1v1=m2v2
v1=1/3.v2 [ since, m1=3.m2 ]
m2=m1/ 3
Answer:
one-third the velocity of Object 2
Explanation:
explain how an earthquake can occur, and briefly describe the forces involved and the effects they have on Earth's crust far from where the earthquake took place. think about how earthquake waves form and travel.
Answer:
When there is sudden movement on the Earth's crust, earthquakes occur. Earthquakes are caused due to sudden lateral or vertical movements in the crust of the Earth. Or we can say that when tectonic plates ride over the other and cause the collision of orogeny or mountain building.
Explanation:
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%
7. An object can be accelerating even if its speed is
constant if it
(a) comes to a stop
(b) is not possible
(C) changes direction
(d) moves in a straight line
Answer:
I think that the answer might be d
Answer:
D
Explanation:
If a car is moving very fast in a straight road or a highway in such a way that it has reached its limits as soon as it is going that fast it can break it limit