Answer:
Jo
Explanation:
irradiating food doesn't make it radioactive (that's contamination) and beta particles are stopped by aluminium foil or thin metals, so it may not pass through thick packaging (usually gamma is used to irradiate foods as it can pass through the packaging)
As a girl pushes and object across a wood floor she suddenly comes to an area where the floor has been waxed recently making it slippery . What becomes true if the coefficient of kinetic friction
Answer:
This question is incomplete but the completed question is below
As a girl pushes an object across a wood floor, she suddenly comes to an area where the floor has been waxed recently, making it slippery. What becomes true of the coefficient of kinetic friction? A. The coefficient of kinetic friction increases. B. The coefficient of kinetic friction decreases. C. The coefficient of kinetic friction becomes zero. D. The coefficient of kinetic friction becomes negative.
The correct option is B
Explanation:
Coefficient of kinetic friction can be defined as the frictional force resisted by the motion of an object. From the question, it might take the girl to apply a force equivalent to just half that of the weight of the object to overcome friction to keep the object moving on a wood floor. Once she gets to the waxed area, the frictional force reduces, thereby also reducing the coefficient of kinetic friction further. Thus, she will be able to use less than half of the force (equivalent to less than half of the weight of the object) to push the object.
Thus, the correct option is B.
How does the construction of dams positively affect natural resources?
by providing water for irrigation and restoring trees to areas where forests once existed
by creating reservoirs, preventing flooding, and renewing destroyed ecosystems
by preventing flooding, creating reservoirs, and providing water for irrigation
by renewing destroyed ecosystems and restoring trees to areas where forest once existed
Other person is incorrect, I did the test on edg.
Answer:
A. by providing water for irrigation and restoring trees to areas where forests once existed
The construction of dams positively affect natural resources by providing water for irrigation.
What is natural resources?Natural resources serves as materials thst is found in nature which are used by humans. These natural substances are soil, water.
Therefore, building of dams can help irrigation by using water which is a natural resources.
Learn more about natural resources at;
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(c) The metal block had a mass of 1.50 kg
The specific heat capacity of the metal was 900 J/kg °C
Calculate the change in thermal energy of the metal during 240 seconds.
Use the Physics Equations Sheet.
Give your answer in kilojoules.
Answer:56
Explanation: I did the test
A squirrel jumps into the air with a velocity of 4 m/s at an angel of 50 degrees. What is the maximum height reached by the squirrel?
Answer:
Explanation:
Assuming the squirrel is jumping off the ground, here's what we know but don't really know...
v₀ = 4.0 at 50.0°
So that's not really the velocity we are looking for. We are dealing with a max height problem, which is a y-dimension thing. Therefore, we need the squirrel's upward velocity, which is NOT 4.0 m/s. We find it in the following way:
[tex]v_{0y}=4.0sin(50.0)[/tex] which gives us that the upward velocity is
v₀ = 3.1 m/s
Moving on here's what we also know:
a = -9.8 m/s/s and
v = 0
Remember that at the very top of the parabolic path, the final velocity is 0. In order to find the max height of the squirrel, we need to know how long it took him to get there. We are using 2 of our 3 one-dimensional equations in this problem. To find time:
v = v₀ + at and filling in:
0 = 3.1 - 9.8t and
-3.1 = -9.8t so
t = .32 seconds.
Now that we know how long it took him to get to the max height, we use that in our next one-dimensional equation:
Δx = [tex]v_0t+\frac{1}{2}at^2[/tex] and filling in:
Δx = [tex]3.1(.32)+\frac{1}{2}(-9.8)(.32)^2[/tex] and using the rules for adding and subtracting sig fig's correctly, we can begin to simplify this:
Δx = .99 - .50 so
Δx = .49 meters
What is the current flowing through the circuit shown? (V= 110 V, R, = 200, R2 = 300, R3 = 10 0) (Ohm's law: V = IR)
A. 1.8 A
B. 20 A
C. 0.05 A
D. 0.55 A
Answer:
A
Explanation:
The first thing you have to do is go back and list the resistances correctly. R1 = 20 R2 = 30 and R3 = 10.
Leave the units off if you can't make an omega.
The resistance of a series circuit (that's what this is) is r1 + r2 + r3 = 10 + 20 + 30 = 60 ohms
Now use ohms law.
R = 60 ohms
V = 110 volts.
I = V / R
I = 110/60
I = 1.833 to the nearest 1/10 = 1.8
(a) What is the escape speed on a spherical asteroid whose radius is 301 km and whose gravitational acceleration at the surface is 0.412 m/s2
Answer:
[tex]V.E=498.02m/s^2[/tex]
Explanation:
From the question we are told that:
Radius [tex]r=301Km[/tex]
Gravitational acceleration [tex]g=0.412 m/s^2[/tex]
Generally the equation for Escape velocity is mathematically given by
[tex]V.E^2=2gr[/tex]
[tex]V.E^2=2*0.412m/s^2*301000[/tex]
[tex]V.E^2=248024[/tex]
[tex]V.E=\sqrt{248024}[/tex]
[tex]V.E=498.02m/s^2[/tex]
If you connected 10 of these 12V (10 W) lamps in parallel, to the 12V source, how much current would the source have to supply
Answer:
[tex]T=8.33A[/tex]
Explanation:
From the question we are told that:
Number of battery [tex]n=10[/tex]
Voltage source[tex]E=12V[/tex]
Lamp Power[tex]P=10W[/tex]
Generally the equation for Resistance is mathematically given by
[tex]R=\frac{V^2}{P}[/tex]
[tex]R=\frac{12^2}{10}[/tex]
[tex]R=14.4ohms[/tex]
Therefore
[tex]R_{eq}=\frac{14.4}{10}[/tex]
[tex]R_{eq}=1.44[/tex]
Generally the equation for Current is mathematically given by
[tex]T=\ffrac{V}{Req}[/tex]
[tex]T=\frac{12}{1.44}[/tex]
[tex]T=8.33A[/tex]
What is an electric fuse? What is the working principle of electric fuse?
A system consists of multiple objects connected by ropes. How many equations need to be written to solve this problem?
A) two for each object
B) one or two for each object
C) one for each object
D) two for the system
Answer:
the correct answer is B
Explanation:
To solve the system they must have the same amount of unknowns as equations,
a) If the system does not have friction, we must write the x-axis equation for each body, therefore we need to write N equations
b) if the system has friction, two equations are needed for each particle
therefore the correct answer is B
help help help please please
Answer:
below
Explanation:
that is the procedure above
Determine the amount of potential energy of a 4.2 kg book that is placed on a shelf with a height of 0.9 meters. Round your answer to one decimal place
Answer:
that is a correct answer maybe .
Mean diameter of cylinder measured by A is 2.50 cm with a possible error of 0.25 cm whereas mean height of cylinder measured by B is 10.0 cm with a possible error of 0.5 cm. Whose measurement is more accurate?
Answer:
The measurement of first cylinder is more accurate.(A)
Explanation:
The least possible error higher will be accuracy.
a.in which portion of the curve,
1. is the velocity uniform.
2.is the velocity increasing.
3.is velocity decreasing.
4.is acceleration zero.
B. at which point does the body start to move and stop.
________________________
I will mark as brainlist
Answer:
the answer is 4 acceleration is 0
Explanation:
this is because when parallel line is drawn through x axis the velocity will bw uniform
plz brainliest
Which two factors affect the size of the gravitational field?
Answer:
Explanation:
mass and distance
Can somebody help me understand this
In 'coin on card' experiment a smooth card is used.
Answer:
In coin card experiment smooth card is used so that the card can slide easily from glass
What is the size of the force acting on a copper wire with a magnetic flux density of 3.6 x 10-2 T acting at
right angles to the wire of length 24 m and current of C:048 A? Give your answer to an appropriate
number of significant figures.
Answer:
F = 0.414 N
Explanation:
Given that,
Magnetic flux density,[tex]B=3.6\times 10^{-2}\ T[/tex]
The length of the wire, l = 24 m
Current, I = 0.48 A
We need to find the force acting on the wire. The formula for the force is given by:
[tex]F=ILB[/tex]
Put all the values,
[tex]F=0.48\times 24\times 3.6\times 10^{-2}\\\\F=0.414\ N[/tex]
So, the force acting on the copper wire is equal to 0.414 N.
The magnetic force of the copper wire is 41.472 N.
Magnetic force of the copper wire
The magnetic force of the copper wire is calculated by applying the following equation.
F = BIL x sinθ
Where;
θ is the inclination of the magnetic fieldI is the currentL is the length of the wireB is the magnetic field strength = flux densityF = (3.6 x 10⁻²) x (48) x 24 x sin(90)
F = 41.472 N
Thus, the magnetic force of the copper wire is 41.472 N.
Learn more about magnetic force here: https://brainly.com/question/13277365
Assertion: When I P+ Q I = I P- QI, then P must be perpendicular to Q. Reason: The relation will hold even when Q is a null vector.
Answer:
The assertion is true and reason is false.
Explanation:
Assertion: I P+ Q I = I P- QI, then P must be perpendicular to Q.
Reason : The relation will hold even when Q is a null vector.
Now
[tex]\left | P + Q \right |=\left | P - Q \right |\\\\P^2 + Q^2 + 2 P Q cos \theta =P^2 + Q^2 - 2 P Q cos \theta\\\\4 P Q cos \theta = 0 \\\\cos \theta = 0 \\\\\theta = 90 degree[/tex]
So, P and Q are perpendicular to each other.
So, the assertion is true.
Reason is false.
A stone is thrown with an initial speed of 12 m/s at an angle of 30o above the horizontal from the top edge of a cliff. If it takes the stone 5.6 s to reach the bottom, how far does the stone travel horizontally
Answer:
[tex]d=58m[/tex]
Explanation:
From the question we are told that:
Initial Speed [tex]U=12m/s[/tex]
Time [tex]T=5.6s[/tex]
Angle [tex]\theta=30[/tex]
Generally the Newton's equation for motion is mathematically given by
[tex]d=d'+ut+\frac{at^2}{2}[/tex]
[tex]d=12cos30*5.6[/tex]
[tex]d=58m[/tex]
A scientist that applies the laws of science to the needs of communities is called _____.
the experimental scientist
the engineer
the teacher
the technician
Answer:
The experimental scientist
the electric charge remains at rest in a. static electricity, b. current electricity, c. none of these
Answer:
Option (a) is correct.
Explanation:
The electric charge is the inherent property of matter which appears due to the deficiency of charge or the excess number of electrons.
There are two types of charges, positive and negative.
When an object has deficiency of charge it becomes positive charge and when it gains some electrons, it becomes negative charge.
When the charge is in motion, it is called electric current and when the charge is at rest, it is called static current.
A charge at rest contributes the electric field only while the charge is in motion contributes the electric and magnetic field both.
The weight of a body is 600 N. What is the mass of the body on the surface of the earth?
Explanation:
soln,
weight=600N
mass=?
gravity=9.8 m/s²
now,
mass=weight/gravitymass=600/9.8mass=61.22kghope it helps.
stay safe healthy and happy.Answer:
m = 61.22 kg
Explanation:
F = 600 N
g = 9.8 m/s²
m = ?
F = mg
600 = m(9.8)
---> m = 61.22 kg
If no braking occurs, a total of how much power would be required to keep the railcar moving at 40 m/s
Answer:
40 kW
Explanation:
A railcar has a continuous 1000 N decelerating force any time it is in motion. If no braking occurs, how much power would be required to keep the railcar moving at 40 m/s
Solution:
Power in Physics is the rate of doing work and the work can be mechanical, electrical, etc. The S.I unit of power is the watts (W).
The power required to keep the car moving must match the work done by the friction force (decelerating force) that tends to slow down the railcar.
Work done = Force * displacement
Power = Work done / time = (Force * displacement) / time
Power = Force * (displacement / time)
Power = force * velocity = 1000 N * 40 m/s = 40000 W
Power = 40 kW
prove that vector addition obeys commutative and associative laws
the order of vector addition doesn't affect the resultant vector and grouping or order of pair doesn't effect the sum.
d. 'g' vanishes at centre of
6) A prism of 6° is made of material of refractive index What is the
deviation caused by it
d. 40
c.120
a. 60
b.8°
7) An object is placed 1cm from lens having magnification 5. Then its foc
length is
a. 0.8 cm b. 1.2 cm c. -1.2 cm d. -0.8cm
Answer:
a. 0.8 cm
Explanation:
The distance of the object from the lens, u = 1 cm
The magnification of the lens, m = 5
The focus of a lens formula is given as follows;
[tex]f = \dfrac{1}{\dfrac{1}{v} + \dfrac{1}{v} }[/tex]
The magnification of the lens, m = -v/u
Where;
v = The distance of the image from the lens
Therefore, we have;
v = m × u
∴ v = 5 × 1 cm = 5 cm (on the other side of the lens)
From which we get;
[tex]f = \dfrac{1}{\dfrac{1}{1} + \dfrac{1}{5} } = \dfrac{5}{6} \approx 0.8[/tex]
The focal length ≈ 0.8 cm
A dog wishes to swim across a slow moving stream. The current velocity is 3.0m/s. The distance directly across the stream is 50m. If the dog point himself directly across the stream, it will take .....
Answer:
Time = 16.667 seconds
Explanation:
Given the following data;
Distance = 50 meters
Velocity = 3 m/s
To find the time it will take;
Velocity can be defined as the rate of change in displacement (distance) with time. Velocity is a vector quantity and as such it has both magnitude and direction.
Mathematically, velocity is given by the equation;
Velocity = distance/time
Making time the subject of formula, we have;
Time = distance/velocity
Time = 50/3
Time = 16.667 seconds
Is torque only produced when the force is applied perpendicular to the moment arm?
The Torque is only produced when the force is applied perpendicular to the moment arm.
What is moment of force?The equal and opposite force acting at a point from the axis of rotation is called the moment.
M = F x r
Moment of force is also called as Torque.
Moment arm is the distance of the point of application of force from the axis of rotation of the body.
Thus, the perpendicular component only, produces the torque.
Learn more about moment of force.
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How much energy does it take to boil water for pasta? For a one-pound box of pasta
you would need four quarts of water, which requires 15.8 kJ of energy for every degree Celsius (°C) of temperature increase. Your thermometer measures the starting
temperature as 48°F. Water boils at 212°F.
a. [1 pts] How many degrees Fahrenheit (°F) must you raise the temperature?
b. [2 pts] How many degrees Celsius (°C) must you raise the temperature?
c. [2 pts] How much energy is required to heat the four quarts of water from
48°F to 212°F (boiling)?
Answer:
a. 164°F
b. [tex]91.\overline 1 \ ^{\circ} C[/tex]
c. [tex]140.\overline 4[/tex] kJ
Explanation:
The starting temperature of the water, T₁ = 48F
The temperature at which the water boils, T₂ = 212°F
a. The difference between the initial and the boiling water temperature, ΔT = T₂ - T₁
Therefore;
ΔT = 212°F - 48°F = 164°F
The temperature by which he temperature must be raised, ΔT = 164°F
b. 48°F = ((48 - 32)×5/9)°C = (80/9)°C = [tex]8.\overline 8 \ ^{\circ} C[/tex]
212°F = ((212 - 32)×5/9)°C = 100°C
∴ ΔT = 100°C - [tex]8.\overline 8 \ ^{\circ} C[/tex] = [tex]9.\overline 1 \ ^{\circ} C[/tex]
c. The heat capacity of the water = The heat required to increase four quartz of water by 1 °C = 15.8 kJ
∴ The heat required to raise four quartz of water by [tex]9.\overline 1 \ ^{\circ} C[/tex], ΔQ = 15.8 kJ/°C × [tex]9.\overline 1 \ ^{\circ} C[/tex] = [tex]140.\overline 4[/tex] kJ.
The power of the kettle was 1.5 kW. The 0.2kg heating element took 5 seconds to heat from 20 °C to 100 °C. Calculate the specific heat capacity of water using this information.
Answer:
Specific heat capacity, c = 468.75 J/Kg°C
Explanation:
Given the following data;
Power = 1.5 kW to Watts = 1.5 * 1000 = 1500 Watts
Time = 5 seconds
Mass = 0.2 kg
Initial temperature = 20°C
Final temperature = 100°C
To find specific heat capacity;
First of all, we would have to determine the energy consumption of the kettle;
Energy = power * time
Energy = 1500 * 5
Energy = 7500 Joules
Next, we would calculate the specific heat capacity of water.
Heat capacity is given by the formula;
[tex] Q = mcdt[/tex]
Where;
Q represents the heat capacity or quantity of heat. m represents the mass of an object. c represents the specific heat capacity of water. dt represents the change in temperature.dt = T2 - T1
dt = 100 - 20
dt = 80°C
Making c the subject of formula, we have;
[tex] c = \frac {Q}{mdt} [/tex]
Substituting into the equation, we have;
[tex] c = \frac {7500}{0.2*80} [/tex]
[tex] c = \frac {7500}{16} [/tex]
Specific heat capacity, c = 468.75 J/Kg°C
Why would an airplane flying at 10,000 meters above the ground have more gravitational potential
energy than the same airplane flying at 1,000 meters above the ground?
Answer:
The gravitational potential energy (gpe) possessed by an object or body is directly proportional to the height of the object or body.
Explanation:
Gravitational potential energy (GPE) is an energy possessed by an object or body due to its position above the earth.
Mathematically, gravitational potential energy is given by the formula;
G.P.E = mgh
Where;
G.P.E represents potential energy measured in Joules.
m represents the mass of an object.
g represents acceleration due to gravity measured in meters per seconds square.
h represents the height measured in meters.
Generally, the gravitational potential energy (gpe) of an object or body is directly proportional to the height of the object or body. Thus, the gravitational potential energy of a body increases as the height of the body increases.
In conclusion, an object with a higher height would have a higher gravitational potential energy.
