Answer:
this is formula
Explanation:
Calculate the power of a person that does 8kJ of work in 4 hours
Answer:
0.56 Watt
Explanation:
Work done = 8 kJ = 8000J
Time = 4 hours = 4*60*60s = 14400sec
Power = ?
Formula of Power is,
Power = Work done / Time
Power = 8000/14400
Power = 0.56 Watt
Hence, Power of person is 0.56Watt.
At what height from the surface of the earth does the value of acceleration due to gravity be 2.45 m/s square where the radius of the earth is 6400 km
Answer:
Explanation: RADIUS OF EARTH = 6400X1000m =
ACC DUE GRAVITY ABOVE SURFACE OF EARTH = g' =2.45 m/s^2
ACC DUE GRAVITY ON SURFACE OF EARTH =g= 9.8 m/s^2
A/C TO FORmULA
g'/g=1-2h/Re
g'/g +2h/Re = 1
2h/Re =1- g'/g
2h= (1- g'/g)Re
2h=(1-2.45 /9.8)
6400X1000
2h = (0.75)6400X1000
2h = 4800000
h= 2400000
m
In a hard disk drive, a constant torque of 14 N⋅m is applied to the magnetic disk when the drive starts recording data. The magnetic disk has a mass of 0.2 kg and radius 2m. Determine the magnitude of the angular acceleration of the disk? [please solve if you know]
The magnitude of the angular acceleration of the magnetic disk is determined as 35 rad/s².
Angular acceleration of the disk
The angular acceleration of the disk is determined from the principle of conservation of angular momentum as follows;
τ = Iα
where;
α is angular acceleration
I is moment of inertia of the disk
I = 0.5MR²
I = 0.5 x 0.2 x 2²
I = 0.4 kgm²
τ = Iα
α = τ/I
α = (14)/(0.4)
α = 35 rad/s²
Learn more about angular acceleration here: https://brainly.com/question/21278452
#SPJ1
A roller coaster car moving at a velocity of 30 meters/second has a momentum of 2.5 × 104 kilogram meters/second. what is its mass? a. 85 kilograms b. 8.3 × 102 kilograms c. 7.6 × 102kilograms d. 7.6 × 103 kilograms e. 7.6 × 104 kilograms
The mass of a rollercoaster car moving at a velocity of 30 meters/second and has a momentum of 2.5 × 104 kilogram meters/second is 8.3 × 10²kg.
How to calculate mass?The mass of the roller coaster car can be calculated using the following formula:
P = m × v
Where;
P = momentumm = massv = velocitym = 2.5 × 10⁴ ÷ 30
m = 8.3 × 10²kg
Therefore, the mass of a rollercoaster car moving at a velocity of 30 meters/second and has a momentum of 2.5 × 104 kilogram meters/second is 8.3 × 10²kg.
Learn more about mass at: https://brainly.com/question/19694949
#SPJ1
can someone do this for me please?! Just the answer pls
Problem 2
Answer: Choice D only
Explanation:
Let's go through the list of possible answers
A) She only would feel a force pulling her toward the chair, hence making her feel heavier, only when the space ship is accelerating faster. In this case, she is moving a constant speed of 0.5c (aka half the speed of light). Despite going this fast, she is moving at a constant speed and therefore not accelerating at this current time. The speed isn't changing. Therefore, she would not feel a force pushing her into the chair. Choice A is off the list.B) This is also off the list as well. The lack of accelerating force means her lungs aren't compressed and breathing should be normal. This is assuming she doesn't have any medical conditions hindering her breathing. We can cross choice B off the list.C) This is similar to choice B. We can cross it off the list.D) The faster you go, the more time dilation will occur. This effectively compresses time and makes it slow down. The more detailed explanation involves relativity which is very complicated. Therefore, choice D is the answer.E) This is false because choice D was mentioned to be true.ditto sound waves espace room answers please I need this urgently
The actual question should be did the sound waves escape room?
Yes they can escape the room
Sound always needs a medium to travel throughIf you close the room form all where that even air can't go outside you will be able to hear no sound coming from room .how much heat is given off when 210.0g of water at 0 degrees freezes into ice?
In the freezing physical change, when 210.0 g of water a 0 degrees freezes into ice, it gives off 71.0 kJ of heat.
What is freezing?It is a physical change in which liquids give off heat to form solids.
We have 210.0 g of water at 0°C. We can calculate the amount of heat given off when it freezes into ice using the following expression.
Q = ΔH°fus × m
Q = 0.334 kJ/g × 210.0 g = 70.1 kJ
where,
Q is the heat released.ΔH°fus is the latent heat of fusion.m is the mass.In the freezing physical change, when 210.0 g of water a 0 degrees freezes into ice, it gives off 71.0 kJ of heat.
Learn more about freezing here: https://brainly.com/question/40140
#SPJ1
whats does 14.600 oz = to in grams
Given that 1 ounce equals 28.35 grams, the value of 14.600 ounces in grams is approximately 413.9g.
What is the value of 14.600 oz in grams?Note that:
1 ounce = 28.35 grams
Given that;
Value of mass = 14.600 ozValue of mass in gramsSince 1 ounce = 28.35 grams, 14.600 oz will be;
14.600 oz = ( 14.600 × 28.35) grams
14.600 oz = 413.9g
Given that 1 ounce equals 28.35 grams, the value of 14.600 ounces in grams is approximately 413.9g.
Learn more about conversion of ounces to gram here: https://brainly.com/question/1117493
#SPJ1
2 large parallel plates are 2.0 cm apart. the strength of the electric plates between them is 100.0 n/c . what is the difference in the voltage between them?
Hello!
We can use the following equation for the potential difference between two parallel plates given an electric field and separation distance:
[tex]V = Ed[/tex]
V = Potential Difference (? V)
E = Electric field strength (100.0 N/C)
d = distance between places (0.02 m)
Plug in the values and solve.
[tex]V = (100)(0.02) = \boxed{2 V}[/tex]
1750 N irregular beam is hanging horizontally by its ends from the ceiling by two vertical wires (A and B), each 1.25 m long and weighing 0.290 N. The center of gravity of this beam is one-third of the way along the beam from the end where wire A is attached. If you pluck both strings at the same time at the beam, what is the time delay between the arrival of the two pulses at the ceiling
The time delay between the arrival of the two pulses at the ceiling is 2.33 ms.
What is center of gravity?Any object of mass is attracted towards another by point where whole mass is supposed to be concentrated is called center of gravity.
A 1750 N irregular beam is hanging horizontally by its ends from the ceiling by two vertical wires (A and B), each 1.25 m long and weighing 0.290 N.
The center of gravity of this beam is one-third of the way along the beam from the end where wire A is attached.
Taking moments about one end, to find the tension at other end.
Tb X L = WxL/3
here, W is the weight, L is the length of wire and Tb is the tension at point B.
So, Tb = W/3
and
Tb - Ta = W
here, Ta is the tension in end A.
Substitute the values, we get
Tb = 583.33N and Ta = 1166.66N
Velocity of end A, Va = (1166.66 x1.25 x 9.81/0.290 )^(1/2)
Va = 222 m/s
Velocity of end B, Vb = (583.33 x1.25 x 9.81/0.290 )^(1/2)
Va = 157 m/s
Time delay t is related with the velocities as
t = L/Vb - L/Va
Substitute the values, we get
t= 0.00233 s
t = 2.33 ms
Thus, time delay between the arrival of the two pulses at the ceiling is 2.33 ms.
Learn more about center of gravity.
https://brainly.com/question/20662235
#SPJ1
A machine is used to convert heat energy into work energy, and is connected to a cooling system which keeps the machine at a constant temperature. If 2000 kJ of heat energy enter the machine, and the machine performs 700 kJ of work,
how much heat energy must still be removed by the cooling system?
Remember What the law of Conservation of energy says about the total energy before and after a transformation.
The amount of heat energy that must still be removed by the cooling system is 1300 kJ.
Conservation energyThe total energy before and after a transformation must be equal.
Based on this principle, the heat energy that must still be removed by the cooling system is calculated as follows;
Input heat energy = out put heat energy
E = h + w
2000 kJ = h + 700 kJ
1300 kJ = h
Thus, the amount of heat energy that must still be removed by the cooling system is 1300 kJ.
Learn more about heat energy here: https://brainly.com/question/7541718
#SPJ1
Cool air tends to...
A. Be less dense and flow over warm air.
B. Be lifted up by more dense warm air.
C. Be more dense and flow under warm air.
D. Mix easily with warm air masses.
Answer: C. Be more dense and flow under warm air.
Explanation:
think of a supermarket selling dairy products and when you open the fridge to get the milk, outside the supermarket is hot and inside the fridge is cold ice.
Supplementary units are dimensionless. Give reasons
Answer:
Supplementary units are the dimensionless units that are used along with the base units to form derived units in the International system.
Explanation:
Since they have no units under SI system, they can be considered dimensionless.
Hope it helps you :))))
have a good day
Which type of rays have a wavelength shorter than that of visible light?
A.
microwaves
B.
infrared rays
C.
gamma rays
D.
radio waves
Answer:
c
Explanation:
wavelength shorter means energy is higher
the wavelength
radio waves>microwave>infrared rays>gamma rays
I just need the formula solved
Answer:
55 kg
Explanation:
Formula :
Force = mass × acceleration
=========================================================
Given :
⇒ Force = 220 N
⇒ acceleration = 4 m/s²
===========================================================
Solving :
⇒ 220 N = mass × 4 m/s²
⇒ mass = 220/4
⇒ mass = 55 kg
Sheila weighs 60 kg and is riding a bike. Her momentum on the bike is 340 kg • m/s. The bike hits a rock, which stops it completely and throws Sheila forward onto the pavement.
If there is no net force on the system, what is Sheila’s velocity immediately after she is thrown from the bike?
1.8 m/s
2.0 m/s
5.0 m/s
5.7 m/s
From the calculation, Sheila’s velocity immediately after she is thrown from the bike is 5.7 m/s.
What is momentum?Momentum is the product of mass and velocity. We know that the momentum before collision is equal to the momentum after collision.
Hence;
Momentum before collision = 340 kg • m/s.
Momentum after collision = 60v
Thus;
340 kg • m/s = 60v kg • m/s
v = 340 kg • m/s/60 Kg
v = 5.7 m/s
Learn more about momentum:https://brainly.com/question/24030570
#SPJ1
A ball is dropped and accelerates downwards at a rate of 10m/s^2 for 12 seconds how much will the ball's velocity increase by?
Answer:
120 m/s
Explanation:
acceleration = velocity/time
10m/s^2 = velocity / 12seconds
10*12 = velocity
120m/s = velocity
A woman raises window blinds by
pulling down on the cord. How is
this changing the amount of work
done on the blinds?
A. The work is harder by changing the amount of
force applied.
B. The work is harder by changing the direction
of the force.
C. The work is easier by changing the direction
of the force.
D. The work is easier by increasing the time the
force is applied.
The raising of window blinds is changing the amount of work done because work is easier by changing the direction of the force.
What is work done?Work done refers to the product of component of a force in the direction of distance and the magnitude of this distance.
According to this question, a woman raises window blinds by pulling down on the cord.
The work done on the blind is made easier because load is relieved by changing the direction of the force.
Learn more about work done at: https://brainly.com/question/13662169
#SPJ1
What is an object's acceleration if it is moving at 40 m/s and comes to a stop in 5 s?
An object's acceleration if it is moving and comes to a stop in 5 s will be 8 m/s².
What is acceleration?Acceleration is defined as the rate change of velocity with time.
acceleration a = (Δv) / (Δt)
An object is moving with initial velocity u = 40 m/s and it comes to stop, then its final velocity v= 0 m/s.
Time taken for the change in speed t=5s.
The acceleration is given by
a = (40 -0)/ 5
a = 8 m/s²
Thus, the object's acceleration is 8 m/s².
Learn more about acceleration.
https://brainly.com/question/12550364
#SPJ1
Anna sets up the circuit shown using a resistor, an LDR and a battery. She finds that when she shines a torch on the LDR the voltage across the resistor increases. Explain why the voltage increases.
The voltage across the resistor increases because extra electron gained by the LDR when the light is shone on it.
Increase in the voltage
Increase in the voltage can occur due to some of the following reasons.
From Ohm's law voltage is directly proportional to current flowing in a circuit.
V ∝ I
The voltage across the resistor increases because extra electron gained by the LDR when the light is shone on it.
Learn more about voltage here: https://brainly.com/question/1176850
#SPJ1
If a car is traveling along a highway at a speed of 30 meters/second, what distance will it cover in one minute?
A.
0.5 meter
B.
2 meters
C.
90 meters
D.
180 meters
E.
1,800 meters
Answer:
E......1,800 meters
Explanation:
distance = speed × time
convert 1 min to seconds because speed is give in meters per seconds so it's which is 60 seconds
Then...60 ×30 = 1,800
What is the frequency of a photon of emr with a wavelength of 2.55x10-3m?
Answer:
f = 1.18 x 10¹¹ Hz
Explanation:
The equation used to find frequency is:
f = c / w
In this form, "f" represents the frequency (Hz), "c" represents the speed of light (3.0 x 10⁸ m/s), and "w" represents the wavelength (m).
Since you have been given the value of the constant (c) and wavelength, you can substitute these values into the equation to find frequency.
f = c / w <---- Formula
f = (3.0 x 10⁸ m/s) / w <---- Plug 3.0 x 10⁸ in "c"
f = (3.0 x 10⁸ m/s) / (2.55 x 10⁻³ m) <---- Plug 2.55 x 10⁻³ in "w"
f = 1.18 x 10¹¹ Hz <---- Divide
According to ohm’s law, resistance is equal to voltage divided by.
Answer:
current
Explanation:
According to ohm’s law, resistance is equal to voltage divided by current.
Answer:
According to ohm’s law, resistance is equal to voltage divided by current.
Explanation:
R = resistance
V = voltage
I = current
R = V/I
hope this helps!! p.s. i really need brainliest :)
calculate the work done in kilo joules in lifting a mass of 20kg at steady velocity through a vertical height of 20m
Answer:
[tex]\huge\boxed{\sf Work\ done = 4 kJ}[/tex]
Explanation:
Since work done is in the form of potential energy, we will use the formula of potential energy here.
We know that,
P.E. = mghWhere,
m = mass = 20 kg
g = acceleration due to gravity = 10 m/s²
h = vertical height = 20 m
So,
Work done = mghWork done = (20)(10)(20)
Work done = 4000 joules
Work done = 4 kJ
[tex]\rule[225]{225}{2}[/tex]
What are the spectral type, temperature, absolute magnitude number, and luminosity of
star a?
The spectral type is B, the temperature is 18,000, the absolute magnitude is 0 and the luminosity is 100.
What is luminosity?The value of luminosity is independent of an observer's distance from an object since it is an absolute measure of radiant power.
Astronomers commonly express an object's brightness in terms of solar luminosities, with one solar luminosity equaling the luminosity of the Sun.
Hence, the spectral type is B, the temperature is 18,000, the absolute magnitude is 0, and the luminosity is 100.
To learn more about the luminosity refer to;
https://brainly.com/question/14140223
#SPJ1
Under water, Zachary can hear waves that travel with frequencies up to 15,000 Hz. What is the velocity of sound in water if a wave with this frequency has a wavelength of 1.2 m?
Answer:
18 000 m/ s
Explanation:
speed = wavelength * frequency
speed = 1.2 * 15 000 = 18 000 m/s
Comment on the statement "Sharper the curve, more is the bending."
The direction of the angular velocity of the minute hand of a wall-clock is perpendicular to the wall and directed inwards.
The passenger slides away from the centre of the curve.
The angle θ which a cyclist should make with the vertical while taking a circular turn of radius r with velocity v given by
tan θ = v^2/rg
Sharper the curve, smaller is the radius and greater is the value of 0.
Calculate the work done by a crane of power 80,000W in 60 seconds.
Answer:
48MJ
Explanation:
Formula :
Work done = Power × time
============================================================
Given :
⇒ Power = 80,000 W = 80kW
⇒ Time = 60s
=============================================================
Solving :
⇒ Work done = 80kW × 60s
⇒ Work done = 4800kJ
⇒ Work done = 48MJ (megajoule)
How does the circuit change when the wire is added? a closed circuit occurs and makes all bulbs turn off. an open circuit occurs and makes all bulbs turn off. a short circuit occurs and makes bulbs 3 and 4 turn off but keeps bulbs 1 and 2 lit. a short circuit occurs and makes bulbs 1 and 2 turn off but keeps bulbs 3 and 4 lit.
The circuit change when a wire is added is, an open circuit occurs and makes all bulbs turn off.
What is a closed circuit?A closed circuit is a type of circuit connection in which the wire connection is complete and current flow occurs, turning the light bulbs on in the process.
What is an open circuit?An open circuit is a type of circuit connection in which the wire connection is incomplete and current cannot flow, turning off the light bulbs.
Thus, the circuit change when the wire is added is, an open circuit occurs and makes all bulbs turn off.
Learn more about open circuit here: https://brainly.com/question/20351910
#SPJ4
Q 29.1 a sheet of copper is placed between the poles of an electromagnet with the magnetic field perpendicular to the sheet. when the sheet is pulled out, a considerable force is required, and the force required increases with speed. explain. is a force required also when the sheet is inserted between the poles? explain.
(a) The force required to remove the sheet increases with increase in speed due to change in magnetic flux.
(b) The area in the magnetic field changes as the sheet is being put in between the poles. Thus, a force would be required to put the sheets.
Change in magnetic flux
When the sheet is pulled out, from the electromagnet there is change in magnetic flux given as follows;
Ф = BA
where;
B is magnetic fieldA is areaemf = dФ/dt
F = qVB
Thus, the force required to remove the sheet increases with increase in speed due to change in magnetic flux.
Also, the area in the magnetic field changes as the sheet is being put in between the poles. Thus, a force would be required to put the sheets.
Learn more about magnetic flux here: https://brainly.com/question/10736183
#SPJ1