Answer:
A. kilometers
Explanation:
A student uses 80 joules of energy to lift a backpack in a time of 0.75 seconds. How much power
does the student have?
Answer:
P = 106.7 W
Explanation:
Given that,
Work done in lifting a backpack, W = 80 J
It is lifted in 0.75 seconds
We need to find the power of the student. The power of an object is defined as work done per unit time. So,
[tex]P=\dfrac{W}{t}[/tex]
Put all the values,
[tex]P=\dfrac{80}{0.75}\\\\P=106.7\ W[/tex]
So, the power of the student is 106.7 W.
The efficiency of an appliance CAN be more than 100 percent. True or False
Answer:
The answer is true
A scientist wants to spend her summer conducting research on the effects of very cold temperatures on the human body. Which part of the world would be the best place to conduct her summer research?
Answer:
Antarctica
Explanation:
ap3x
Say what main energy change
takes place in the following
examples.
a) clockwork toy
b) boy kicking a football
c) boiling kettle on a gas ring
d) person walking upstairs
Answer:
b) boy kicking a football
Explanation:
it 's because the ball was at rest but when it was kicked, it starts to more
A block of mass 2.5kg is pressed against a spring and compresses the spring to a length of
10.0 cm. Then, the block is released and begins to move to the right as the spring returns
to its natural length of 21.4 cm. The spring has a spring constant of 88 N/m. Using Hooke's
Law, determine the force in the spring.
Pay attention to your units (specifically your values of spring length). Answer in units of
Answer:
10.032 N.
Explanation:
From the question given above, the following data were obtainedb
Mass (m) = 2.5 Kg
Final length = 10.0 cm
Original length = 21.4 cm
Spring constant (K) = 88 N/m
Force (N) =?
Next, we shall determine the compression of the spring. This can be obtained as follow:
Final length = 10.0 cm
Original length = 21.4 cm
Compression (e) =?
e = Original length – final length
e = 21.4 – 10
e = 11.4 cm
Next, we shall convert 11.4 cm to m. This can be obtained as follow:
100 cm = 1 m
Therefore,
11.4cm = 11.4 cm × 1 m / 100 cm
10 cm = 0.114 m
Finally, we shall determine the force. This can be obtained as illustrated below:
Compression (e) = 0.114 m
Spring constant (K) = 88 N/m
Force (N) =?
F = Ke
F = 88 × 0.114
F = 10.032 N
Thus, the force in the spring is 10.032 N
Which of the following best describes how heat is transferred by conduction?
a. Particles in warmer objects make particles in colder objects move faster.
b. Particles in colder objects make particles in warmer objects move slower.
c. Particles in warm and cold objects mix together and transfer energy.
d. Particles move from warmer objects to colder objects.
a. Particles in warmer objects make particles in colder objects move faster.
Part II. True or False 1. Bernoulli's principle is a statement of energy conservation in static fluids. 2. For most solids, the coefficient of volume expansion is proportional to the coefficient of linear expansion. 3. Latent heat of a material does not affect the amount of heat transfer across a slab by conduction. 4. If the net force acting upon a body is zero, the particle is always at rest. 5. A football kicked at an angle 0 with respect to the horizontal means that the acceleration is 9.8m/s2 at all times. 6. Equilibrant force is the combination of all the forces acting on an object. 7. Reflection occurs when there is the presence of medium where light can travel. 8. Diverging Lenses always have negative focal length. 9. The total mechanical energy in the system must always be equal to zero. 10. Electric field is the strongest when it is close to the charged particle creating the field.
Answer:
True 1, 2,3, 6, 8 and 10
False 4, 5, 7 and 9
Explanation:
In this exercise, several situations will be analyzed, to know if they are true/false
1) True. Bernoulli's equation is the conservation of energy
2) True. The volumetric expansion is approximately 4 times the linear expansion
3) True. Latent heat is the heat used in a phase transformation and does not change the temperature of the body and the conduction is proportional to the change in temperature.
4) False. The particle can be at rest or at constant velocity
5) False. Acceleration depends on the force of the kick
6) True. The sum of force must be zero
7) False. Reflection occurs at the interface between two different media
8) True. Diverging lenses the focal length is negative
9) False. Manganic energy is the sum of the energies, therefore it must be different from zero
10) True. The electric field is inversely propositional to the square of the distance
A car accelerates at a rate of 13m/s^2[S]. If the car's initial velocity is 120km/h[N]. What will its final velocity be in m/s, after two seconds.
Answer:
the final velocity of the car is 59.33 m/s [N]
Explanation:
Given;
acceleration of the car, a = 13 m/s²
initial velocity of the car, u = 120 km/h = 33.33 m/s
duration of the car motion, t = 2 s
The final velocity of the car in the same direction is calculated as follows;
v = u + at
where;
v is the final velocity of the car
v = 33.33 + (13 x 2)
v = 59.33 m/s [N]
Therefore, the final velocity of the car is 59.33 m/s [N]
What is the characteristic of image formed by a convex lens that is placed at the focal length of the lens?
Answer:
The image will be real, inverted, and enlarged. For convex lenses, when the object is placed inside F, the image will be on the same side of the lens as the object and it will be virtual, upright, and enlarged.Feb
For every 120 joules of energy input a car wastes 85 joules , find the useful energy output of the car ?
Answer:
35 Joules
Explanation:
Applying
Input Energy(Q) = Useful energy output(U)+Wasted Energy(W)
Q = U+W.............................. Equation 1
Make U the subject of the equation
U = Q-W................... Equation 2
From the question,
Given: Q = 120 Joules, W = 85 Joules
Substitute these values into equation 2
U = 120-85
U = 35 Joules
Help please, with #18, it’s a basketball question
Answer: D
Explanation:
Answer:
C. A lob pass.
Hope this helps!!
How does a magnet exert a force without touching
another object?
Magnets create a field of influence that
attracts or repels magnetic objects.
Magnets physically make objects move.
Someone must make a magnet force stuff
to move.
Answer:
Magnets create a field of influence that
attracts or repels magnetic objects.
Explanation:
Hope it helps :)
Answer: The magnet has a magnetic field that either attracts or repels another magnet or magnetic metal. It is because of this magnetic field that things move.
Explanation: N/A
What amount of energy is needed for an electron to jump from n = 1 to n = 4?
Answer:
[tex]E=2.04\times 10^{-18}\ J[/tex]
Explanation:
We need to find the energy for an electron to jump from n = 1 to n = 4.
The energy in transition from 1 state to another is given by :
[tex]E=\dfrac{-2.18\times 10^{-18}}{n^2}\ J[/tex]
The difference in energy for n = 1 to n = 4 is:
[tex]E=-2.18\times 10^{-18}\times (\dfrac{1}{4^2}-1)\\\\E=2.04\times 10^{-18}\ J[/tex]
So, the required energy is equal to [tex]2.04\times 10^{-18}\ J[/tex].
How many tons of paper did Americans recycle in 2018? _______________. Show your work below:
Answer:
46 million tons
Explanation:
i dont know what im suppose to explain
unit of speed is derived unit why
Answer:
Explanation:
Therefore, the unit of speed is the meter per second, or m/s. The unit meter per second is called a derived unit, meaning that it is derived from the seven SI base units.
Answer:
Derived SI Units
Explanation
In physics there are many quantities that cannot be expressed by a single base unit. ... Therefore, the unit of speed is the meter per second, or m/s. The unit meter per second is called a derived unit, meaning that it is derived from the seven SI base units.
HELP! block is released from rest and slides down a frictionless ramp inclined at 30' from the horizontal. When the block reaches the bottom the block-Earth system has mechanical energy Eo The
experiment is repeated, but now horizontal and vertical forces of magnitude F are exerted on the block while it slides, as shown above. When the block reaches the bottom, the mechanical energy
of the block-Earth system
A) is greater than Eo
B)is equal to Eo
C)is less than Eo
D)cannot be determined without knowing
Answer:
A
Explanation:
the horizontal and vertical force acting on it consist a net force on the inclined direction (30degrees below the horizontal) you can tell by the length of the horizontal component (try to see the 30degree incline as horizontal, because that's the direction of the displacement). net work done on the system results in an increase in energy. i hope this can help :D, i'm also taking the ap physics 1 exam tommorow.
When the block reaches the bottom, the mechanical energy of the block-Earth system is greater than Eo.
The given parameters:
Inclination of the ramp, θ = 30⁰The work - done on the block is calculated as follows;
[tex]W = F d \times cos(\theta)[/tex]
where;
d is the displacement of the blockWhen the block reaches the bottom, the displacement increases.
Based on work-energy theorem, as the work done increases, the mechanical energy increases as well.
Thus, when the block reaches the bottom, the mechanical energy
of the block-Earth system is greater than Eo.
Learn more about work-energy theorem here: https://brainly.com/question/22236101
How does sound travel from its source to your ear?
(a) by changes in air pressure
(b) by vibrations in wires or strings
(c) by electromagnetic waves
(d) by infrared waves
Answer:
The answer is B
Explanation:
a sample contains 110 g of a radioactive isotope. how much radioactive isotope will remain in the sample after 1 half-life?
a. 100g
b. 25 g
c. 75 g
d. 50 g
Answer:
The half-life of a radioactive isotope is the time such that the initial amount of the isotope is reduced to its half.
Thus, if we start with A grams of a given radioactive isotope, after a 1 half-life, we will have A/2 grams of the radioactive isotope.
In this case, we know that the sample has 110g of a radioactive isotope.
Then, after 1 half-life, we should have half of 110g, which is:
110g/2 = 55g
Then we should have 55 g of a radioactive isotope.
The answer that is closer to this result is option d (50 g), so that is the correct one.
Students make the claim that Jupiter is the warmest gaseous planet.
Which data best supports this claim?
A. Jupiter has the greatest diameter.
B. Jupiter is the most massive planet.
C. Jupiter has the greatest equatorial gravity.
D. Jupiter is the closest outer planet to the Sun.
Answer:D. Jupiter is the closest outer planet to the Sun.
[tex]\tt \: \pink {Option \: D}[/tex]
[tex]:\implies[/tex]Jupiter is the closest outer planet to the Sun.
The power of crane is 30000 watt. What work will be done by it in 10 sec?
Explanation:
power =work done/time
work=power ×time
work =30000×10
work =300000j
stay safe healthy and happy.Tyra made the following bar graph shown to represent the relative distances of four different astronomical bodies from Earth.
The title of the bar graph is Distance of Bodies in Space from Earth. Four bars are labeled A, B, C, and D. Bar C is the shortest. Bar D is about three times the size of bar C. Bar A is about six times the size of bar C. Bar B is about eight times the size of bar C.
If D represents Mercury, which of the following could be represented by B and C?
B could be the moon, and C could be Venus.
B could be Venus, and C could be the moon.
B could be the moon, and C could be Jupiter.
B could be Jupiter, and C could be the moon.
Answer: D
Choice A calls B the moon which is incredibly tiny compared to Venus so this is wrong, choice B calls B Venus which is a relatively small planet and C the moon... that is a bit overkill so no. Choice C says B is the moon and C is Jupiter, Jupiter being the largest planet this is a easy no, leaving D to be the only logical and correct answer.
Explanation: MARK ME BRAINLIEST PLZZZZZZZZZZzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
Answer: Answer D. because B. Jupiter is the farthest from Earth from those answer choices and C. is the moon because it is the closest out of those answer choices.
So, the answer is D: B could be Jupiter, and C could be the moon.
Explanation: Please give Brainlist.
Hope this helps!!!!
A gas has four moles under a pressure of 5.4 atm has a volume of 120 L. What is the
temperature of the gas? (1 atm = 101325 Pa, 1 L = 0.001 m3
)
____________________________________________________
Answer:
1973. K
Explanation:
PV=nRT
(5.4)(120)=(4)(0.0821)T
648=(0.3284)T
1973. = T
Using the ideal gas equation, T is measured in Kelvin.
Or, you could isolate T:
T = PV/nR
The answer is the same.
The half‐life of Uranium‐237 is 5.83 x 10^5 seconds. What is the decay constant?
Answer:
λ = 1.19 x 10⁻⁶
Explanation:
The relationship between the half-life of an element and the decay constant of that element is given by the following formula:
[tex]T_{1/2} = \frac{0.693}{\lambda} \\\\\lambda = \frac{0.693}{T_{1/2}}[/tex]
where,
[tex]T_{1/2}[/tex] = half-life = 5.83 x 10⁵ s
λ = decay constant = ?
[tex]\lambda = \frac{0.693}{5.83\ x\ 10^5\ s}[/tex]
λ = 1.19 x 10⁻⁶
Uniformly charged ring with 180 nC/m and radius R= 58 cm. Find the magnitude of the electric field in KN/C at a point P on the axis of the ring at distance 116 cm from its center.
Answer:
3.135 kN/C
Explanation:
The electric field on the axis of a charged ring with radius R and distance z from the axis is E = qz/{4πε₀[√(z² + R²)]³}
Given that R = 58 cm = 0.58 m, z = 116 cm = 1.16m, q = total charge on ring = λl where λ = charge density on ring = 180 nC/m = 180 × 10⁻⁹ C/m and l = length of ring = 2πR. So q = λl = λ2πR = 180 × 10⁻⁹ C/m × 2π(0.58 m) = 208.8π × 10⁻⁹ C and ε₀ = permittivity of free space = 8.854 × 10⁻¹² F/m
So, E = qz/{4πε₀[√(z² + R²)]³}
E = 208.8π × 10⁻⁹ C × 1.16 m/{4π8.854 × 10⁻¹² F/m[√((1.16 m)² + (0.58 m)²)]³}
E = 242.208 × 10⁻⁹ Cm/{35.416 × 10⁻¹² F/m[√(1.3456 m² + 0.3364 m²)]³}
E = 242.208 × 10⁻⁹ Cm/35.416 × 10⁻¹² F/m[√(1.682 m²)]³}
E = 6.839 × 10³ Cm²/[1.297 m]³F
E = 6.839 × 10³ Cm²/2.182 m³F
E = 3.135 × 10³ V/m
E = 3.135 × 10³ N/C
E = 3.135 kN/C
When will electric charges flow?
A. When the circuit is open.
B. When the circuit is incomplete.
C. When the circuit is closed.
D. When the switch is off.
Answer:
A
Explanation:
Can anyone answer this its a science question NO LINKS!!!
Answer:
The correct answer is C I took the mastery test
Explanation:
Answer:
d last one
Explanation:
Help please!!
What are the three criteria that determine if a wave is a sound wave?
Answer:
Wavelength, Amplitude, Time-Period, Frequency and Velocity or Speed.
Explanation:
Sound wave can be described by five characteristics: Wavelength, Amplitude, Time-Period, Frequency and Velocity or Speed. The minimum distance in which a sound wave repeats itself is called its wavelength. That is it is the length of one complete wave
Answer: Sound wave can be described by five characteristics: Wavelength, Amplitude, Time-Period, Frequency and Velocity or Speed.
Explanation:
The minimum distance in which a sound wave repeats itself is called its wavelength. That is it is the length of one complete wave.
Where was the first FIFA World Cup held?
(HINT: The host country won the tournament
Answer:
The 1930 FIFA World Cup was the inaugural FIFA World Cup, the world championship for men's national association football teams. It took place in Uruguay from 13 to 30 July 1930.
Explanation:
hope it helps if so pls give it the brainliest answer
Answer:
[tex]\huge\boxed{Uruguay\hookleftarrow}[/tex]
⎇ The first FIFA World Cup Championship took place in Uruguay from from 13 July 1930 to 30 July 1930.
help! im timed. A ball is thrown downward with an initial velocity of 12.1 m/s. How long will it take to reach a velocity of -24.5 m/s?
Answer:
[tex]1.27\:\text{s}[/tex]
Explanation:
We can use the following kinematics equation to solve this problem:
[tex]v_f=v_i+at[/tex]
Solving for [tex]t[/tex]:
[tex]-24.5=-12.1+-9.8t,\\-12.4=-9.8t,\\t=\frac{-12.4}{-9.8}\approx \boxed{1.27\:\mathrm{s}}[/tex]
which statement correctly describes the relationship between a black body radioterapia it’s tmeptaute and the electromagnic radiation it gives off
Answer:
Hi
Explanation:
Radiation therapy is commonly applied to the cancerous tumor because of its ability to control cell growth. Ionizing radiation works by damaging the DNA of cancerous tissue leading to cellular death. To spare normal tissues (such as skin or organs which radiation must pass through to treat the tumor), shaped radiation beams are aimed from several angles of exposure to intersect at the tumor, providing a much larger absorbed dose there than in the surrounding healthy tissue