Answer:
n =1.33 revolutions
Explanation:
Uniform Circular Motion
The angular speed can be calculated in two different ways:
[tex]\displaystyle \omega=\frac{v}{r}[/tex]
Where:
v = tangential speed
r = radius of the circle described by the rotating object
Also:
[tex]\omega=2\pi f[/tex]
Where:
f = frequency
Solving for f:
[tex]\displaystyle f=\frac{\omega}{2\pi}[/tex]
Since the frequency is calculated when the number of revolutions n and the time t are known:
[tex]\displaystyle f=\frac{n}{t}[/tex]
We can solve for n:
n=f.t
The particle moves in a circle of r=90 m with a speed v=25 m/s. Thus the angular speed is:
[tex]\displaystyle \omega=\frac{25}{90}[/tex]
[tex]\displaystyle \omega=0.278\ rad/s[/tex]
Now we calculate f:
[tex]\displaystyle f=\frac{0.278}{2\pi}[/tex]
[tex]f=0.04421\ Hz[/tex]
Calculating the number of revolutions:
n = 0.04421*30
n =1.33 revolutions
A.Specific heat capacities of three different substances are given below:
Substances
Specific heat capacity
A
910 J/kg °C
B
380 J/kg °C
C
470 J/Kg °C
1.What do you mean by specific heat capacity of A is 910 J/kg °C?
2.Which above given substance will gain least temperature while heating equal mass
of all the three substances supplied with equal amount of heat? Give reason.
3.Which one will go down least in depth while keeping equal mass at the three
substances heated for the same temperature of 100 °C and kept on a wax slab, why?
Answer:
1)substance A will require 910 J of heat to increase the temperature by 10°C.
2) Substance B
3) Substance A
Explanation:
1) The meaning of the statement: "specific heat capacity of A is 910 J/kg °C" is that 1 kg of substance A will require 910 J of heat to increase the temperature by 10°C.
2) While heating equal mass of all the three substances supplied with equal amount of heat, Substance B will gain more temperature due to the fact that substances of lesser specific heat capacity always tend to gain or loose heat within a short period of time.
3) While keeping equal mass at the three substances heated for the same temperature of 100°C and kept on a wax slab, substance A will go down more in depth due to the fact that heat is preserved for a longer period of time for substances that have higher specific heat capacity.
A car is moving at 20 m/s. The driver steps on the gas pedal and accelerates the car for 4 seconds at an acceleration of 4 m/s2. How fast is the car moving after it accelerates?
Answer:
The final velocity of the car is 36 m/s.
Explanation:
Given;
initial velocity of the car, u = 20 m/s
time of the car acceleration, t = 4 s
acceleration of the car, a = 4 m/s²
the final velocity of the car is calculated as;
v = u + at
where;
v is the final velocity of the car
v = 20 + (4 x 4)
v = 36 m/s
Therefore, the final velocity of the car is 36 m/s.
Hey, can you help me?
Answer:
The unit rate is $0.22 lb
Explanation:
The given parameters are;
The price for 18 lb = $3.99
We have;
The unit rate is the price for one unit. Whereby the unit of measurement is the lb, we have that one unit = 1 lb.
Therefore, given that 1 lb = 18 lb/18, the price of 1 lb which is the unit rate is given as follows;
18 lb price = $3.99
Divide both sides by 18 to get;
18 lb/18 = $3.99/18 = $0.221[tex]\bar 6[/tex]
Therefore, we have;
1 lb = 18 lb/18 = $0.221[tex]\bar 6[/tex]
The unit rate, which is the cost for 1 lb to the nearest hundredth = $0.22/lb.
if vector A =i+2j-k and vec A cross vec B =3i-j+5k. find vec B
Let B = a i + b j + c k. Then the cross product of A = i + 2j - k with B is
A × B = ( i + 2j - k ) × ( a i + b j + c k )
A × B = a ( i × i ) + 2a ( j × i ) - a ( k × i )
… … … + b ( i × j ) + 2b ( j × j ) - b ( k × j )
… … … + c ( i × k ) + 2c ( j × k ) - c ( k × k )
A × B = 0 - 2a k - a j
… … … + b k + 0 + b i
… … … - c j + 2c i - 0
A × B = (b + 2c) i + (-a - c) j + (b - 2a) k
So we have
3 i - j + 5 k = (b + 2c) i + (c - a) j + (b - 2a) k
which gives us the system of equations,
{ b + 2c = 3
{ -a - c = -1
{ -2a + b = 5
Solve for a, b, and c.
• Eliminate c from the first two equations:
(b + 2c) + 2 (-a - c) = 3 + 2 (-1)
-2a + b = 1
But -2a + b = 5, and 5 ≠ 1, so there is no such vector B that satisfies the cross product!
A gun recoils back when the bullet is fired ,why?
A gun recoils back when the bullet is fired due to conservation of momentum. Conservation of momentum suggest that - the net change of momentum in a closed system must be zero.
Therefore in equation form -
[tex]mv - mu = 0[/tex]
Why does a gun recoil when a bullet is fired?
Explanation:When a bullet is fired, the gun exerts a force on the bullet through the trigger (this is action) in a particular direction. According to Newton's Third Law, we know to every action there is an equal and opposite reaction; action and reaction act on different bodies. So, the bullet will also exert an equal and opposite reaction on the gun in the opposite direction. That is why a gun recoils when a bullet is fired from it.
Hope it helps.ray4918 here to helpWhich of these waves has the greatest wavelength? Group of answer choices Wave shown with 2 wavelengths. Wave shown with 3 wavelengths. Wave shown with 1 wavelength stretch over a short distance. Wavelength shown with 1 wavelength stretched over a long distance.
Answer:
This question is incomplete
Explanation:
This question is incomplete because of the absence of the figure. However, wavelength can be described as the distance between two crests (identical points) of a wave (as illustrated in the picture attached). Thus, a wave with a large/great wavelength must have a long distance between the two crests and has nothing to do with the number of crests/wavelengths since distance between crests could also be small.
Hence, what appears to be the correct option is the last option (Wavelength shown with 1 wavelength stretched over a long distance).
Answer:
Its B.
Explanation:
Im took the exam.
How much force would be needed to
push a 22 kg box across the floor with
an acceleration of 1.9 m/s^2? Assume
that there is a coefficient of friction of.
17 between the box and the floor.
Help me with this!!!!!!!it’s due in 10 minutes
There would be two forces acting on the box parallel to the floor, with a net force of
∑ F = p - f = m a
where p = magnitude of the push, f = mag. of friction, m = mass of the box, and a = acceleration. To find p, we first need f .
There are also only two forces acting on the box perpendicular to the floor, with net force
∑ F = n - w = 0
where n = mag. of normal force of the floor on the box and w = weight of the box. The net force is 0 because the box is only accelerating parallel to the floor.
w = m g, where g = 9.8 m/s² is the mag. of the acceleration due to gravity, so we can solve for n :
n = w = m g
n = (22 kg) (9.8 m/s²)
n = 215.6 N
The kinetic friction is proportional to the normal force by a factor of the given coefficient of friction, µ = 0.17, such that
f = µ n
f = 0.17 (215.6 N)
f = 36.652 N
Now solve for the required pushing force:
p - 36.652 N = (22 kg) (1.9 m/s²)
p ≈ 78 N
Answer:
0
Explanation:
Is the gravity on the moon and earth the same and why are they the same or different
what is the correct answer?
Answer:
length=2
Explanation:
You simply find the zeros of the quartic polynomial
The factored form is (x+1)(x-5)(x-2)=0
The zeros become -1,5 and 2
Dimension 5 is already given and the question says length>width and 2>-1
Therefore length=2
Which statement best describes an electric current?
A Energy transfers inside of an electric device.
B Charged particles move
through a conductor.
C Type of conductor or insulator.
D The measurement of the electric potential energy in a circuit.
Answer:
its B
Explanation:
the movement of charged particles in a conductor
Charged particles move through a conductor best describes an Electric current.
What is Electric current?A stream of charged particles, such as electrons or ions, traveling through an electrical conductor or a vacuum is known as an electric current.
Charge carriers, which can be any of a number of particle kinds depending on the conductor, are the moving particles. Electrons flowing over a wire are frequently used as charge carriers in electric circuits.
They can be electrons or holes in semiconductors. Ions are the charge carriers in an electrolyte, whereas ions and electrons are the charge carriers in plasma, an ionized gas.
Therefore, Charged particles move through a conductor best describes an Electric current.
To learn more about electric current, refer to the link:
https://brainly.com/question/2264542
#SPJ2
All models have a limitations True or false
Answer:
The answer is True.
uh guys so i forgot everything that i took in physics and now i a question, whats p=mv
p stands what?
Answer:
P is momentum.
Explanation:
Brainliest Please!!?!!
- ElizabethKate.
1. The coin remains at rest in the figure shown. This is due to
(a) inertia of rest
(b) two forces act on the coin which balance each other
(c) no unbalanced force acts on it
(d) all of these
A bus travels east for 3 km, then north for 4 km. What is its final displacement?
5 km southeast
5 km northwest
5 km northeast
5 km southwest
Explain how itis possible for electron-group geometry to difer trom molecular geometry. Use the Lewis dot diagram below to help in your explanation
Answer:
If lone pairs of electrons, electrons not bonded to other atoms, are located in the molecule, this will change the molecular geometry, not the electron geometry. If all the electron groups are bonded, with no lone pairs, then the electron geometry and molecular geometry are the same.
How does variation impact natural selection?
Heat from a fire warming your hands is an example of
Answer:
Thermal energy is the total kinetic energy of moving particles of matter, and the transfer of thermal energy is called heat. Thermal energy from the bonfire is transferred to the hands by thermal radiation. ... This is how the fire warms the hands of someone sitting near the bonfire.May
Answer:
Thermal Radiation
Explanation:
Type of heat transfer Hope this helped <3
what is the reason behind superposition?why waves behave this way?
Explanation:
Most waves appear complex because they result from two or more simple waves that combine as they come together at the same place at the same time—a phenomenon called superposition. Waves superimpose by adding their disturbances; each disturbance corresponds to a force, and all the forces add
introurself please
deduce the relation between kwh and joule define 1 watt
Explanation:
We know that kWh is a commercial unit of energy.
Also, 1 Joule = 1 watt × 1 seconds
[tex]1\ kWh=1kW \times 1\ h[/tex]
Since ,1 h = 3600 s and 1kW = 1000 W
[tex]1\ kWh=1000\ W \times 3600\ s\\\\1\ kWh = 36\times 10^5\ W-s\\\\1\ kWh=36\times 10^5\ J[/tex]
So, the relation is : [tex]1\ kWh=36\times 10^5\ J[/tex]
1 watt is defined as the power of an appliance when the energy is transferred at a rate of 1 Joule per second.
1) Think of planting a tree. You dig the hole, put it in, and fill it back in. Next,
you need to attach 3 ropes to the tree to try to keep it straight while it grows.
You put the ropes on it like a "V". Where do you have to put the third rope to
ensure your tree is straight?
Answer:
at the top of the tree I hope it will help you please follow me
WHICH ONE IS IT????
RINGS
POINT
GRAPH
READS
TALKS
Answer: c or b
Explanation:
Please help me with this question please
What machine changes electrical energy into light and sound energy?
battery
o lightbulb
alarm dock
apple
Answer:
light bulb
Explanation:
What do the lysosomes do? (check all that apply)
A) clean the cell
B) ship products
C) destroy foreign objects
D) provides energy for the cell
Answer:
I think its A
Explanation:
A lysosome is a membrane-bound cell organelle that contains digestive enzymes. Lysosomes are involved with various cell processes. They break down excess or worn-out cell parts. They may be used to destroy invading viruses and bacteria.
The function of lysosomes is to remove waste as well as destroying a cell after it has died, called autolysis. A lysosome is an organelle containing digestive enzymes which it uses to function as the digestion and waste removal for cells, food particles, bacteria, etc.
if the angle of refraction is 20 degrees what is the angle of incidence
Answer:
13.1
Explanation:
that's what I'm gonna go with, but u can research more
what is the correct answer?
Answer:
4
Explanation:
I added all of them and them minus the 5.
Psychology:
Retrograde amnesia is the memory loss of events that occurred after the onset of amnesia.
True or False
It’s false.
Answer:
thank you
Explanation:
Answer:
False is correct
Explanation:
Peace and Love
A Geosynchronous orbit is one where a satellite orbits the earth with the same period of motion as the earth on its own axis.
How far from the center of the earth is the satellite's orbit?
Answer:
22236 mi
Explanation:
2km south is a measure of what
The answer Is kilometers
A helicopter flies over the arctic ice pack at a constant altitude, towing an airborne 137-kg laser sensor that measures the thickness of the ice (see the drawing). The helicopter and the sensor both move only in the horizontal direction and have a horizontal acceleration of magnitude 2.63 m/s2. Ignoring air resistance, find the tension in the cable towing the sensor. Incorrect: Your answer is incorrect.
Answer:
The value is [tex]T = 1702.91 \ N[/tex]
Explanation:
From the question we are told that
The mass of the laser sensor is [tex]m = 137 \ kg[/tex]
The horizontal acceleration of the helicopter and the sensor is [tex]a = 2.63 \ m/s^2[/tex]
Generally the net force on the cable is
[tex]F = T - W = ma[/tex]
Here W is the weight of the sensor which is evaluated as [tex]W = m * g = 137 * 9.8 = 1342.6 \ N[/tex]
So
[tex]T - 1342.6 = 137 * 2.63[/tex]
=> [tex]T = 360.31 + 1342.6[/tex]
=> [tex]T = 1702.91 \ N[/tex]