Answer:
5
Explanation:
The light intensity may be defined as the strength of the light or the magnitude of its brightness that a source of light can produce.
The light threshold is the minimum intensity of the light that our eye can detect and the ability to adapt to darkness.
In the context, Daniel wishes to find if can notice the difference in the intensity of the light when he add 5 candles to the set of 50 candles.
He noticed that when he added 5 candles, he could notice the difference in the intensity and when he added less than 5 candles to the set of 50 candles he could not detect.
Thus, the difference threshold for Daniel to detect the change in the intensity of the light is 5 candles.
A piece of iron has a mass of 30 g and its volume is 6.2 cm3. What is its density?
Answer:
Density = 4.84 g/cm³
Explanation:
Given the following data;
Mass = 30 g
Volume = 6.2 cm³
To find the density of the piece of iron;
Density can be defined as mass all over the volume of an object.
Simply stated, density is mass per unit volume of an object.
Mathematically, density is given by the equation;
[tex]Density = \frac{mass}{volume}[/tex]
Substituting into the equation, we have;
[tex]Density = \frac{30}{6.2}[/tex]
Density = 4.84 g/cm³
which of the following is incorrect for nuclear forces
a) they are attractive in nature
b) they are short range forces
c) they obey inverse square law
d) they are non conservative in nature
Answer:
c they obey inverse square law
The specific heat capacity of sea water is 4100 J/Kg°C and the boiling point of 100.6 °C. (i) Calculate the energy required to raise the temperature of 0.900 kg of this sea water from 10 °C up to its boiling point. Also mention the equation to be used. *
Answer:
334.314 (kJ)
Explanation:
1) the formula for the required energy is: Q=c*m(Bp-t), where c - 4100 J/kg*C; m - 0.9 kg; Bp - 100.6 C; t - 10 C.
2) according to the formula above:
Q=4100*0.9*(100.6-10)=41*9*906=334314 (J).
As an IT technician for your company, you have been notified that the Windows domain does not seem to be functioning properly. Being familiar with domains, you are fairly confident you know what the issue is. But just to be safe, you take the applicable time to gather additional information and to identify what, if anything, has changed.
Which of the following is the BEST next step?
A. Determine the appropriate fix.
B. Create a hypothesis.
C. Implement the fix.
D. Identify what has changed.
E. Gather information.
Answer: Create a hypothesis
Explanation:
From the information given, information has been gathered and the identification to ascertain if there's a change. Then, an hypothesis has to be created in order to know what the problem is.
One has to carry out some research in order to know what went wrong and should also validate the hypothesis by consulting with ones peers. By doing this, the most likely causes of the issues will be gotten.
What are the wavelengths of x-rays and gamma rays?
a.
x-rays - 3 pm to 20 nm
gamma rays- less than 3 pm
c.
x-rays - 3 mm
gamma rays- 20 to 50nm
b.
x-rays - 400nm
gamma rays- 700nm
d.
None of the above
Answer:
1. less. 2 greater. 3. the same. 8. An FM radio station broadcasts its signal at a fre- ... wave 3. | 3x108 = 269.15x107). = 3.20m. 2. An electromagnetic AM-band radio wave could have Base your answers to questions 9 and 10 on the informa- ... X rays. -Microwaves. -Long
Croquet balls must have a mass of 0.50 kg. A red croquet ball is moving at 5 m/s. It strikes an at-rest green croquet ball head-on and then continues to move in the same direction, but with a speed of 2 m/s. What is the final speed of the green ball?
A.
5 m/s
B.
0.5 m/s
C.
2 m/s
D.
3 m/s
Answer:
Explanation:
The Law of Momentum Conservation for us has the equation
[tex][m_rv_r+m_gv_g]_b=[m_rv_r+m_gv_g]_a[/tex] and filling in:
[tex][(.50)(5.0)+(.50)(0)]=[(.50)(2.0)+(.50)v_g][/tex] and
2.5 = 1.0 + .50v and
1.5 = .50v so
v = 3 m/s
The final speed of the green ball is 3m/s. This can be calculated by the law of conservation of momentum. Thus, the correct option is D.
What is the law of Conservation of Momentum?
The principle of the law of conservation of momentum states that if any two objects undergo collision, then the total momentum of the objects before and after the collision will be the same if there is no external force acting on the colliding objects.
The Law of Conservation of Momentum has the equation which is:
m₁ × u₁ + m₂ × u₂ = m₁ × v₁ + m₂ × v₂
where, m₁ = mass of object 1,
u₁ = initial velocity of object 1 before collision,
m₂ = mass of object 2,
v₁ = final velocity of object 1 after collision,
v₂ = final velocity of the object 2 after collision.
0.50 × 5 + 0.50 × 0 = 0.50 × 2 + 0.50 × v₂
2.5 + 0 = 1.0 + 0.50 × v₂
2.5 - 1.0 = 0.50 × v₂
1.5 = 0.50 × v₂
1.5/ 0.5 = v₂
v₂ = 3m/s
Therefore, the correct option is D.
Learn more about Momentum here:
https://brainly.com/question/24030570
#SPJ2
Water is being heated on the stove at 90 ⁰C. What is this temperature on the Fahrenheit degrees?
Answer:
194 degrees farenheit! hot
Explanation:
(90°C × 9/5) + 32 = 194°F
Answer:
194
Explanation:
to get from celcius to Fahrenheit
multiply temperature by 2 and add 30
NEED ANSWER QUICK, WILL GIVE BRAINLIEST! How many nails do sapiens have?
A. 6
B. 10
C. 3
D. None
Answer:
nice calculations!
Explanation:
Q= Which one of the following statement is incorrect?
A. When a switch is closed in a circuit, no current flows.
B. A switch is a device for turning on and off an electric current.
C. An electric current is a complete loop around which a current can flow.
D. An electric current is a flow of charge
Answer:
A.
Explanation:
I think it might be the big number A
1d. Conservation of energy is demonstrated in this roller coaster example.
The Conservation of Energy is a principle which states that energy cannot be created
or destroyed, but can be altered from one form to another
Friction plays a significant role in the efficiency of the rollercoaster cars. Explain how, even
with friction, the law of conservation of energy still holds true. (2 points)
Answer:
can you clear your question I can't understand
50N force accelerated a body at a rateof 8 metres per second square. Calculate the mass of the body
Answer:
m=6.25kg
Explanation:
Force= mass × acceleration
50=m×8
make m subject of the formula...
m=50/8
m=6.25kg
Answer:
[tex]\boxed {\boxed {\sf 6.25 \ kilograms}}[/tex]
Explanation:
According to Newton's Second Law of Motion, force is the product of mass and acceleration.
[tex]F= m \times a[/tex]
We know the force is 50 Newtons and the acceleration is 8 meters per second squared. Let's convert the units to make the problem and unit cancellation easier.
1 Newton is equal to 1 kilogram meter per square second (1 kg*m/s²), so the force of 50 N is equal to 50 kg*m/s².
Now we know 2 values:
F= 50 kg*m/s²a= 8 m/s²Substitute the values into the formula.
[tex]50 \ kg *m/s^2= m \times 8 \ m/s^2[/tex]
Since we are solving for the mass, we must isolate the variable, m. It is being multiplied by 8 meters per square second and the inverse of multiplication is division. Divide both sides by 8 m/s².
[tex]\frac {50 \ kg *m/s^2}{8 \ m/s^2}= \frac{m \times 8 \ m/s^2}{8 \ m/s^2}[/tex]
[tex]\frac {50 \ kg *m/s^2}{8 \ m/s^2}= m[/tex]
The units of meters per square second (m/s²) cancel.
[tex]\frac {50 \ kg }{8 }=m[/tex]
[tex]6.25 \ kg =m[/tex]
The mass is 6.25 kilograms.
In a wire, when elongation is 4 cm energy stored is E. if it is stretched by 4 cm, then what amount of elastic potential energy will be stored in it?
4E
Explanation:The elastic potential energy of an elastic material (e.g a spring, a wire), is the energy stored when the material is stretched or compressed. It is given by
U = [tex]\frac{1}{2}kx^2[/tex] --------------------(i)
Where;
U = potential energy stored
k = spring constant of the material
x = elongation (extension or compression of the material).
From the first statement;
when elongation (x) is 4cm, energy stored (U) is E
Substitute these values into equation (i) as follows;
E = [tex]\frac{1}{2}k(4)^2[/tex]
E = 8k
Make k subject of the formula
k = [tex]\frac{E}{8}[/tex] [measured in J/cm]
From the second statement;
It is stretched by 4cm.
This means that total elongation will be 4cm + 4cm = 8cm.
The potential energy stored will be found by substituting the value of x = 8cm and k = [tex]\frac{E}{8}[/tex] into equation (i) as follows;
U = [tex]\frac{1}{2}\frac{E}{8} (8)^2[/tex]
U = [tex]\frac{1}{2}{8E}[/tex]
U = [tex]{4E}[/tex]
Therefore, the potential energy stored will now be 4 times the original one.
Explain why magnetic damping might not be effective on an object made of several thin conducting layers separated by insulation.
Answer:
The eddy currents will be very small.
Explanation:
An object made of several thin conducting layers separated by insulation may not be affected by magnetic damping because the eddy current produced in each layer due to induction will be very small and the opposing magnetic flux produced by the eddy currents will be very small.
Based on the law of conservation of energy, how can we reasonably improve a machine’s ability to do work?
Answer:
We can reasonably improve a machines ability to do work by reducing the friction between the moving parts of machine.
Explanation:
According to the law of conservation of energy, the energy can neither be created nor destroyed.
An athlete running the velocity 3m/s due east is confronted with two trade winds. One wind travelling at 10m/s in a direction north 65degrees east and another wind travelling at 8m/s in a direction south 70degrees east. Find the resultant velocity and direction of the athlete
Answer:
v = 10.09 m / s, 8.78 North of East
Explanation:
The easiest way to solve this exercise is to decompose the velocities into a coordinate system, where the x-axis coincides with the West-East direction and the y-axis coincides with the South-North direction.
athlete's velocity v₁ₓ = 3 m / s
wind speed 2 v₂ = 10 m / s with direction 65 north of east
sin 65 = v_{2y} / v₂
cos 65 = v₂ₓ / v₂
v_{2y} = v₂ sin 65
v₂ₓ = v₂ cos 65
v_{2y} = 10 sin 65 = 9.06 m / s
v₂ₓ = 10 cos 65 = 4.23 m / s
wind speed 3 v₃ = 8 m / s with direction 70 south of east
This angle measured from the positive side of the x-axis is
θ = 360 - 70
θ = 290
sin 290 = v_{3y} / v₃
cos 290 = v₃ₓ / v₃
v_{3y} = v₃ sin 290
v₃ₓ = v₃ cos 290
v_{3y} = 8 sin 290 = -7.52 m / s
v₃ₓ = 8 cos 290 = 2.74 m / s
now we can find each component of the velocity
X axis
vₓ = v₁ + v₂ₓ + v₃ₓ
vₓ = 3 + 4.23 + 2.74
vₓ = 9.97 m / s
Y axis
v_y = v_{2y} + v_{3y}
v_y = 9.06 - 7.52
v_y = 1.54 m / s
to find the modulus let's use the Pythagorean theorem
v = [tex]\sqrt{v_x^2 + v_y^2 }[/tex]
v = [tex]\sqrt{9.97^2 + 1.54^2}[/tex]
v = 10.09 m / s
let's use trigonometry for the direction
tan θ = v_y / vₓ
θ = tan⁻¹ v_y / vₓ
θ = tan-1 1.54 / 9/97
θ = 8.78
the address is 8.78 North of East
Find the magnitude and angle of a vector given the components: Bx = 7, By=-5
Answer:
[tex] |B| = \sqrt{ {B _{x} }^{2} + {B _{y} }^{2} } \\ = \sqrt{ {7}^{2} + {5}^{2} } \\ = \sqrt{74} \\ = 8.6[/tex]
[tex]let \: the \: angle \: be \: \theta \\ \tan(\theta) = \frac{B _{y} }{B _{x} } \\ \tan( \theta) = \frac{ - 5}{7} \\ \theta = { \tan }^{ - 1} ( \frac{ - 5}{7} ) \\ = 35.5 \degree[/tex]
what happens when a light ray is incident normally to the interface of two media?
Explanation:
ahhh, maybe you mean , what happens when a light ray hits the interface of two media perpendicular to the normal.
if that is the case then the light ray will not bend but it will travel in the same direction in the second medium as it was travelling in it's first medium
hope this helps bro
Why does the soccer ball not increase in size when air is pumped into it?
Answer:
(I'm not 100% sure about this)
Maybe its because the soccer ball is faulty. Such troublemakers can include holes in the ball, preventing it from inflating.
a ball of mass 0.2 kg is dropped from a height of 20m on impact to the ground it loses in 30 joule of energy calculate the height it reaches on rebound
Answer:
new PE at top=original PE - energy lost
mgh=.2(9.8)20-30
Explanation:
mgh=.2(9.8)20-30 = 9.2
what the balance electrons for calcium
Answer:
its two valence electrons
Explanation:
Calcium is a group 2 element with two valence electrons. Therefore, it is very reactive and gives up electrons in chemical reactions.
UR WELCOME!! :)
Thermal physics vs atomic physics ...which is easier?
Answer:
Thermal physics
Explanation:
Because it uses temperature
Answer:
In my opinion both are easier if you'll work hard on it...
(b) How much energy must be supplied to boil 2kg of water? providing that the specific latent heat of vaporization of water is 330 kJ/kg.
Complete question:
(b) How much energy must be supplied to boil 2kg of water? providing that the specific latent heat of vaporization of water is 330 kJ/kg. The initial temperature of the water is 20 ⁰C
Answer:
The energy that must be supplied to boil the given mass of the water is 672,000 J
Explanation:
Given;
mass of water, m = 2 kg
heat of vaporization of water, L = 330 kJ/kg
initial temperature of water, t = 20 ⁰C
specific heat capacity of water, c = 4200 J/kg⁰C
Assuming no mass of the water is lost through vaporization, the energy needed to boil the given water is calculated as;
Q = mc(100 - 20)
Q = 2 x 4200 x (80)
Q = 672,000 J
Q = 672,000 J
Q = 672,000 J
Therefore, the energy that must be supplied to boil the given mass of the water is 672,000 J
(I have 2 questions which are very similar)
Which of the chemical reactions above stores energy?
A. Cellular respiration
B. Photosynthesis
C. Both cellular respiration and photosynthesis
D. Neither cellular respiration nor photosynthesis
15 Which of the chemical reactions above releases energy?
A. Cellular respiration
B. Photosynthesis
C. Both cellular respiration and photosynthesis
D. Neither cellular respiration nor photosynthesis
(help!!!) SCIENCE
Answer:
B
A
Explanation:
please mark as brainliest :)
A spring with a spring constant of 200 is compressed 0.5 . What is the potential energy stored in the spring
Answer:
E = 25 J
Explanation:
Given that,
Spring constant, k = 200
Compression, x = 0.5
We need to find the potential energy stored in the spring. The formula for the stored potential energy in the spring is given by :
[tex]E=\dfrac{1}{2}kx^2[/tex]
Put all the values,
[tex]E=\dfrac{1}{2}\times 200\times 0.5^2\\\\E=25\ J[/tex]
So, 25 J of potential enersy is stored in the spring.
the gravity on mars is 3.8 m/s2 and you weigh 200 N. your mass will be??
Answer:
Mass = 52.63 kilograms
Explanation:
Given the following data;
Acceleration due to gravity = 3.8 m/s²
Weight = 200 N
To find mass;
Mathematically, the weight of a physical object is given by the formula;
Weight = mass * acceleration due to gravity
Substituting into the formula, we have;
200 = mass * 3.8
Mass = 200/3.8
Mass = 52.63 kg
[tex]\boxed{\color\red\huge\tt\bold\purple{Question}}[/tex]
Define Inertia.
Answer:
Inertia : a property of matter by which it continue in its existing state of rest or uniform motion in a straight line, unless that state is changed by external force.
HOPE ITS HELPS!!
[tex]\boxed{\color{red}\huge\tt\bold\purple{Answer}}[/tex]
Inertia is the tendency of an object to continue in the state of rest or of uniform motion. The object resists any change in its state of motion or rest.
A 15.0 kilogram cart initially traveling at 2.0 meters per second east accelerates uniformly at 0.75 meter per second squared east for 6.0
seconds. What is the speed of the cart at the end of this 6,0 second interval? Please include all work - including givens, formula, substitution,
and units for full credit. (2)
Answer:
Explanation:
Since this is not parabolic motion, it is one-dimensional motion. Very simple. What we are given is
mass: 15.0 kg
initial velocity: 2.0 m/s
acceleration: .75 m/s/s
time: 6.0 seconds
Since we are looking for final velocity, the equation we need for this is
v = v0 + at that says final velocity is equal to the initial velocity plus the acceleration of the object times how long it travels. We don't have a need for the mass here at all.
[tex]v=2.0\frac{m}{s}+.75\frac{m}{s^2}(6.0s)[/tex]
Notice that one of the seconds labels to the right of the plus sign cancel out, leaving us with like units...which we HAVE to have if we want to add.
Simplifying a bit gives us
v = 2.0 m/s + 4.5 m/s so
v = 6.5 m/s
A rocket of mass M when empty carries a mass M of fuel. The rocket and fuel travel at speed v.
The engine of the rocket is fired and all of the fuel is expelled. The speed of the rocket increases
to 2v.
What happens to the kinetic energy of the rocket?
A It doubles.
B It halves.
C It increases by a factor of four.
D It stays the same.
The kinetic energy of the rocket should be A. it doubles.
What is kinetic energy?Kinetic energy represents the energy where an object or a particle should be the reason for its motion. It transfers energy than it should be done on an object by applying a net force, so the object speeds up and thereby gains kinetic energy. In the case when the speed increased to 2v so the kinetic energy should also doubles.
Learn more about speed here: https://brainly.com/question/17052831
What would be the weight (in Newtons) of a person with a mass of 80 kg on Earth, where the acceleration due to gravity is approximately 9.8 m/s/s? *
please help asap
Answer:
ml tayo 1v1 durugin kita
Explanation:
ano takot ml 1v1
The reading on your speedometer is the
A) average velocity
B) none of these is correct
C) speed
D) instantaneous velocity