a child has the kinetic energy of 71 j the mass of the child is 27kg show that the velocity of the child at this point is 2.3m/s
Explanation:
kinetic energy of child = 1/2 m v^2
71 j. = 1/2×27kg ×v^2
71×2/27= v^2
142/27 = v^2
5.3. =v^2
v= √5.3
v= 2.3 m/s
2. Summarize how to use a spring scale to measure a pull and how to use it to apply a push with
a specific force.
If the spring constant is known, the extension or compression of the spring can be used to calculate the applied force (pull or push) on the spring.
According to Hook's law, the force applied to an elastic material is directly proportional to the extension of the material.
The force applied;
F = kx
where;
k is the springThe applied force can be in form of push or pull. A push force can result in compression of the spring while a pull force can result in extension of the spring.
If the spring constant is known, the extension or compression of the spring can be used to calculate the applied force (pull or push) on the spring.
Learn more here:https://brainly.com/question/4404276
Which of the following explains why NASA mandated that space food could NOT crumble or come apart?
Crumbs may cause electronics to malfunction.
There is no way to clean crumbs, so all food must be contained.
Floating crumbs may get into astronauts’ eyes.
Crumbs increase the risk of bacteria development.
Answer:
C.
Floating crumbs may get into astronauts’ eyes.
why are some small jovian planet moons geologically active?
Answer:
tidal heating and/or their composition
Explanation:
....................................
Answer:
yeah
Explanation:
What are Newtons Laws famous for
Answer:
Why are Newton's laws of motion important? Newton's laws of motion are important because they are the foundation of classical mechanics, one of the main branches of physics. Mechanics is the study of how objects move or do not move when forces act upon them.
As the temperature of an air mass increases, its atmospheric pressure______. Group of answer choices
Answer:
its atmospheric pressure decreases
When the temperature of an air mass increases, its atmospheric pressure drops
ok done. Thank to me :>
A box of mass 6.0 kg is accelerated from rest
across a floor at a rate of 6.0 m/s² for 9.0 s.
Find the network done on the box
[tex]\text{Given that },\\\text{Mass, m = 6 kg}\\\\\text{Acceleration, a = 6 } \text{m} \text{s}^{-2}\\\\\text{Time, t=9 sec}\\\\\text{Displacement, }s=ut + \dfrac 12 at^2 = \dfrac 12 at^2 = \dfrac 12 \times 6 \times 9^2 = 243 ~m}\\\\\ \text{Work,} ~W = Fs = mas = 6 \times 6 \times 243 = 8748 ~ J}[/tex]
Hi there!
We know that:
[tex]W = \Delta KE = \frac{1}{2}m(\Delta v)^2[/tex]
We can begin by solving for the final velocity using the equation:
[tex]v_f = v_i + at[/tex]
The box starts from rest, so:
[tex]v_f = at\\\\v_f = 6(9) = 54 m/s[/tex]
Now, we can find the kinetic energy:
[tex]KE = \frac{1}{2}mv^2\\\\KE = \frac{1}{2}(6)(54^2) = 8748 J[/tex]
Thus:
[tex]W = \Delta KE\\\boxed{W = 8748 J}[/tex]
If the mass of the Earth is doubled, how will the moon’s orbit be affected?
What Would Happen to the Orbit of the Moon if it Were Twice as Massive? ... The orbit would not change.
HOPE IT HELPS:)
PLS FOLLOW:)
#BRAINLIEST:)
A car accelerates from 20m/s to 30m/s in 10 sec. Find the cars acceleration using v=u+at
Explanation:
we derive the formula of acceleration using the formula so v - u /t so
30-20/10
so the acceleration is 1 m/s square
Please find attached photograph for your answer.
Hope it helps.
Do comment if you have any query.
What is a lever?....
Answer:
A lever is a simple machine in the subject "S.T.E.M"
Explanation:
Levers use the following forces in order to be used: push or pull.
examples are crow bars,shovels, brooms and ect.
explique ¿por que un objeto que tiene energía es capaz de realizar un trabajo?
Which of these is a unique use of beta particles?
A. CT scanners
B. Tracing chemicals in the environment C. Killing bacteria
D. Smoke detectors
Answer:
The answer is A, CT scanners.
a comet or asteroid impact on the earth is a frequently suggested cause for many of the mass extinctions. for which of the major mass extinctions does the most evidence exist that this was the main trigger for the event?
Answer:
Cretacious-Tertiary
Explanation:
I hope this helps!
Which one of the following is not a vector quantity? a) Displacement b ) density c) force d) vecocity
Answer:
density
Explanation:
density is a scalar quantity having only magnitude and no info about derection
negatively charged particles of radiation emitted from the decay of radioactive substances are known as
Answer: beta particles
Explanation:
that's the answer
pls help me do these physic questions
Answer:
1 since it is meatl and sharp
2 since it is sharp and iron
a device that converts mechanical energy into electricity is a
Answer:
An electric generator is a device that converts a form of energy into electricity.
Explanation:
Which of the followng is Newton's Second Law?
a. An object in motion will stay in motion unless acted upon by an unbalanced outside force
b .Force = mass times acceleration
c.When one object puts a force on the another object, the second object puts a force back on the first, equal in magnitude and opposite in direction
Answer:
A
Explanation:
The kinetic energy of an object can sometimes be greater than a potential energy a originally possessed, true or false?
Answer:
true
Explanation:
Energy stored in the nuclei of atoms can be used to generate electricity. ... Most of the energy of food is converted to heat.
the thermodynamic processes that occur in nature ____________.
Answer:
The thermodynamic processes that occur in nature convert thermal energy into mechanical energy.
The thermodynamic processes that occur in nature are according to the law of thermodynamics.
The thermodynamics processes seen in nature are guided by the law of thermodynamics. The role of energy and heat transmission in physical systems is guided by these laws.
The laws are:
(1) Energy cannot be created nor destroyed in a system, according to the first law of thermodynamics, Also, referred to as the law of energy conservation. Only from one form to another, the energy can be transmitted or altered. Energy is conserved through natural processes, keeping the overall amount constant.
(2) Second law of thermodynamics: states that the overall entropy of an isolated system tends to increase over time in any natural process. This suggests that processes progress towards a state of increasing disorder.
Hence, the thermodynamic processes are guided by the law of thermodynamics.
To learn more about Thermodynamics, here:
https://brainly.com/question/33845440
#SPJ6
A ball is falling toward the ground. Which of the following statements are false? (a) The force that the ball exerts on Earth is equal in magnitude to the force that Earth exerts on the ball. (b) The ball undergoes the same acceleration as Earth. (c) The magnitude of the force the Earth exerts on the ball is greater than the mag- nitude of the force the ball exerts on the Earth.
Hi there!
(A) The force that the ball exerts on Earth is equal in magnitude to the force that Earth exerts on the ball.
Gravitational force is an example of an action-reaction pair:
[tex]F_{1,2} = -F_{2,1}[/tex]
Gravitational force is given by the equation:
[tex]F_g = \frac{Gm_1m_2}{r^2}[/tex]
Plugging in the masses of the Earth and ball, gravitational constant, and radius will result in the SAME GRAVITATIONAL FORCE exerted by both objects on each other.
A large solar farm has 21 700 solar panels and generates 5.0 MW of power.
1.0 MW = 1.0 × 106 W
Calculate the average power each panel produces.
Answer:
answer is
Explanation:
average power each panel produces = 21700/ 5×10^6
4340 ×10^-6
that's mean 4340 micro Watt
The energy transferred per unit electric charge in a circuit is .
A current
B charge
C power
D potential difference
Answer:
(D)
E = V Q energy of charge Q thus V = E / Q
If two stars are in a binary system with a combined mass of 5.5 solar masses and an orbital period of 12 years, what is the average distance between the two stars
The average distance between the two stars is 792 light years
Let the mass of the first star be [tex]m_1[/tex]
Let the mass of the second star be [tex]m_2[/tex]
The combined mass of the two stars, [tex]m_1+m_2=5.5[/tex] solar masses
The orbital period of the stars, P = 12 years
Average distance between the two stars, D = ?
The average distance between the two stars can be calculated using Kepler's equation
[tex]D=(m_1+m_2)P^2[/tex]
Substitute [tex]m_1+m_2=5.5[/tex] and P = 12 into the formula [tex]D=(m_1+m_2)P^2[/tex]
[tex]D=5.5(12^2)[/tex]
D = 5.5(144)
D = 792 light years
Learn more here: https://brainly.com/question/25490228
Which factor is not a type of spectra?
A.
emission
B.
absorption
C.
continuous
D.
discontinuous
A child is stationary on a swing.(a)The child is given a push by his brother to start him swinging.His brother applies a steady force of 84 N over a distance of 0.25 m.(i) Calculate the work done by this force.(2)..............................................................................................................................................(ii) State how much energy is transferred by this force.(1)..............................................................................................................................................(iii) After several more pushes, the child has a kinetic energy of 71 J.The mass of the child is 27 kg.Show that the velocity of the child at this point is about 2.3 m/s.(2)(iv) Which one of these quantities changes in both size and direction while he is swinging?Put a cross ( ) in the box next to your answer.(1)Ahis gravitational potential energyBhis momentumCthe force of gravity acting on himDhis kinetic energy
Answer:
Work done = Fs
Explanation:
(i) W = Fxs
= 84N x0.25m
= 21 Joules
(ii) Ek = 1/2mv^2
71 = 1/2×27×v^2
71×2/27 = v^2
v = 23m/s
The work done by this force is 21 Joule.
Energy transferred by the force is 21 Joule.
The boy's momentum changes periodically, that is, in both size and direction.
What is force?An external force is an agent that has the ability to change the resting or moving condition of a body. It has a direction and a magnitude. So, it is a vector quantity. Newton is the SI unit of force (N).
(i) Given parameter:
Steady force applied by his brother, F = 84 N.
Displacement, d = 0.25 m.
The work done by this force, W = F.d = 84×0.25 = 21 Joule.
(ii) Amount of work done is transferred by this force as an energy. So, amount of energy transferred by the force is 21 Joule.
(iii) Given parameter:
Mass of the child, m= 27 kg.
Kinetic energy, E = 71 J.
Let, velocity of the child = v, then kinetic energy is,
E = 1/2 × mv²
⇒ v = √(2E/m)
= √(2×71/27)
= 2.3 m/s.
Hence, the velocity of the boy is 2.3 m/s. (proved).
(iv) During swing, his velocity changes periodically. That's why, his momentum changes periodically, that is, in both size and direction.
Learn more about force here:
https://brainly.com/question/13191643
#SPJ2
The mass of the hammer is 0.454 kg. Calculate the weight of the hammer.
Explanation:
weight =0.454 × 9.8=4.4492N
Answer:
4.45 n sorry if I am wrong
if you exert a force on an object, but the object remains stationary as you apply the force, then how much work have you done on the object?
Answer:
no work done
Explanation:
unless you moved the object
When we apply a force on an object, but the object remains at rest when the force is applied, then we have zero work done on the object because the object does not move.
What is Work done?Work done by a force is defined as the product of the displacement and the component of the force exerted by the object in the direction of displacement. Work done is expressed as:
Work done= Force* Displacement
When an object is at rest, there is no external force on it except gravity acting on it, in which case work will be zero because the force acting on it is perpendicular. Thus displacement is zero and if displacement is zero then work done will be zero.
Suppose that displacement is zero then,
W=f×0
Work done is zero
Thus, the work done is zero.
Learn more about Work done, here:
https://brainly.com/question/13662169
#SPJ2
plzz explain how it is 66 m
i know that distance =speed × time so how it is 66 m not a
0.4 and if there us another rule plz explain like if u day that 1/2 ×speed ×time plz explain why u used 1/2 or when do I use the 1/2 rule
Hi there!
For someone to hear an echo, the sound must echo and bounce back to the person.
Thus, the sound travels TWICE the distance from the person to the wall (to the wall and back).
We know that:
d = st (distance = speed × time)
Let L = distance from person to wall
Thus:
2L = st
2L = 330 × 0.40
2L = 132
L = 66 m