Answer:
A. 80 N
Explanation:
Since the uniform plank is pivoted at its center at an angle of 30 to the vertical, then it is 90° - 30° = 60° to the horizontal.
Let L be the length of the plank = 4 m, the perpendicular distance of the 4 kg mass form the pivot point is Lcos60°/2. Then the moment of the 4 kg mass about its pivot point is mgLcos60/2 where m = mass = 4 kg and g = acceleration due to gravity = 10 m/s²
Let F be the force applied at 0.5 m from the pivot point. The perpendicular distance of F from the pivot point is 0.5cos60°. Thus the moment of this force about the pivot point is F × 0.5cos60° = 0.5Fcos60°
Since both moments are the same for equilibrium,
mgLcos60/2 = 0.5Fcos60°
F = mgL/(2 × 0.5 m)
F = 4 kg × 10 m/s² × 4 m/1 m
F = 80 kgm/s²
F = 80 N
Q 36 - URGENT HELP PLS
WILL BE MARKED AS BRAINLIEST.
riding a bicycle and using of wheelbarrow (kariton) are example of
A.fluid friction
B.rolling friction
C.sliding friction
D.static friction
f the voltage in a circuit is 80 volts and the resistance is 20 ohms, what is the current?
I = 4 A
Explanation:
From Ohm's law, the voltage is given by
V = IR
or
I = V/R = (80 V)/(20 ohms)
= 4 A
What is kinetic energy formula???
Answer :— Kinetic energy is directly proportional to the mass of the object and to the square of its velocity: K.E. = 1/2 m v2. If the mass has units of kilograms and the velocity of meters per second, the kinetic energy has units of kilograms-meters squared per second squared.
[tex] \\ [/tex]
Hope you understand :)
Answer:
Explanation:
Kinetic energy (K.E)=1/2*mass*velocity^2
What is velocity?
Please don't answer and let joinbrainly answer. Thank you.
Answer:
The rate of change in position of an object with respect to time, and displacement is called velocity.
At apogee the moon is at its farthest from earth and thus appears smaller than normal. Because of this it has the smallest angular size in the sky at this time. At apogee the moon is at its farthest from earth and thus appears smaller than normal. Because of this it has the smallest angular size in the sky at this time. True False
Answer:
the statement is FALSE
Explanation:
In the movement of celestial bodies the most common orbit is the ellipse, in this the sun orbits or in this case the planet Earth is in a focus and the lighter body rotates around in a closed orbit.
The closest point is called perigee and the farthest apogee, but throughout the movement the kinetic moment must be conserved, so at the farthest point the speed decreases so that the angular momentum remains constant since the radius is greater.
This phenomenon is also described in Kepler's second law as that the areas must be equal in equal periods of time, so the speed decreases when being further from the Earth.
Consequently the statement is FALSE
write a short note on Andromeda galaxy.
Answer:
[tex]\sf\pink{Andromeda \: galaxy}[/tex]
The Andromeda is a galaxy which is nearest to the milky way. It is also named as Messier 31 or M31 or NGC 224. It is a spiral galaxy located at a distance of approximately 2.5 million light years from earth.
another name Andromeda in Hindi is Vaikunth.
Explanation:
The Andromeda Galaxy (IPA: /ænˈdrɒmɪdə/), also known as Messier 31, M31, or NGC 224 and originally the Andromeda Nebula (see below), is a barred spiral galaxy approximately 2.5 million light-years (770 kiloparsecs) from Earth and the nearest major galaxy to the Milky Way.
Number of stars: ~1 trillion (1012)
Right ascension: 00h 42m 44.3s
(give the answer or I'll report) please solve it with the steps
Answer:
The required elastic potential energy is 0.068J
Explanation:
Given,
Spring force constant, k= 3.4 N/M
Spring stretch length/ Displacement, x= 0.2m
We know,
Elastic potential energy, V= [tex]\frac{1}{2} kx^{2}[/tex]
=[tex]\frac{1}{2}*3.4*(0.2)^{2}[/tex]
=[tex]\frac{0.136}{2}[/tex]
=0.068
∴The required elastic potential energy is 0.068J
what is force of gravity
Answer:
On Earth all bodies have a weight, or downward force of gravity, proportional to their mass, which Earth's mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects. At Earth's surface the acceleration of gravity is about 9.8 metres (32 feet) per second per second.
Un proyectil es lanzado con un ángulo de 30⁰ y una velocidad inicial de 20m/s ¿cual es el punto más alto de su trayectoria? ¿cual es su alcanzar horizontal? ¿cuánto tiempo está en el aire¿
Answer:
Thus, the horizontal range is 17.7 m, and the maximum height is 10.2 m.
Explanation:
velocity of projection, v = 20 m/s
Angle of projection, A = 30 degree
The horizontal range is
[tex]R =\frac{v^{2}sin2A}{g}\\R=\frac{20\times 20\times sin60}{2\times 9.8}\\R=17.7 m[/tex]
The maximum height is
[tex]H =\frac{v^{2}sin^{2}A}{2g}\\H=\frac{20\times 20\times sin^{2}30}{9.8}\\H=10.2 m[/tex]
The electric force between two charges increases when
A) both charges become negative
B) both charges become positive
C) the charges get closer together
D) the charges get further apart
Answer:
the charges get closer together
As elevation increases, temperature decreases. At which elevation will sound travel fastest? 500 meters 1,000 meters 1,500 meters 2,000 meters
Answer:
500 meters
Explanation:
Sound travels faster in warmer air because the air particles have more kinetic energy. The highest temperature air is found at the lowest altitude, therefore 500 meters is the elevation that sound travels the fastest from the options provided.
Answer:
500 meters
Explanation:
Waves that are completely out of phase will experience destructive interference.
True
or
False
Answer:
True
Explanation:
As far as I know, constructive interference means waves are "in phase" and destructive interference means the waves are "out of phase"
Answer:
true
Explanation:
destructive interference occurs when two identical waves are superimposed exactly out of phase.
Write a short paragraph about Fruit and Seed formation of Strawberry plants.
What force is exerted on a machine? output force work input work output input force
Answer:
output force is exerted on a machine
Answer:
output force is exerted in the machine , i guess
A force of 20N displaces an object to 5m in 10s. Calculate the power.
Answer:
hope it helps you see the attachment for further information
please help i would really appreciate it
Answer:
Did you try searching it up
Explanation:
An object moving at a constant velocity will always have a
Answer:
It will always have a zero acceleration
hiii can someone please help me with this thank u <//3
Answer:
7: B:
8: A:
9: D:
Explanation:
HOPE IT HELPS YOU!!
Answer:
7. (C) 12 m/s
8. (D) 44.1 m
9. (C) 9.8 m/s^2
Explanation:
8. y = -(1/2)gt^2
= -(1/2)(9.8 m/s^2)(3 s)^2
= -44.1 m
This means the ball traveled 44.1 vertically downwards.
A spring is hung from the ceiling. A 0.442-kg block is then attached to the free end of the spring. When released from rest, the block drops 0.150 m before momentarily coming to rest, after which it moves back upward. (a) What is the spring constant of the spring
Answer:
[tex]K=58.8N/m[/tex]
Explanation:
From the question we are told that:
Mass [tex]M=0.442[/tex]
Drop distance [tex]d=0.150[/tex]
Generally the equation for Spring Constant is mathematically given by
[tex]K=\frac{2mg}{x}[/tex]
[tex]K=\frac{2*0.442*9.8}{1.150}[/tex]
[tex]K=58.8N/m[/tex]
If a chemical spill reaches groundwater, the availability of which resource will be reduced for people in the area?
A. fish
B. drinking water
C. hydroelectric energy
D. geothermal energy
What is the difference between Mass and Weight?
Why do we use mass instead of weight?
hmm.....................
Answer:
could you please translate this
Explanation:
may try to help
Answer:
hmm
Explanation:
AMIAMO, MO SHINDAUO
The Doppler shift can be observed when ____________. Check all that apply. Group of answer choices the source of sound moves towards an observer the source of sound moves away from an observer an observer moves towards a stationary sound source an observer moves away from a stationary sound source the observer and sound source move at the same speed in the same direction the observer and sound source move at the same speed towards one another none of these
Answer:
the source of sound moves towards an observe
Explanation:
The Doppler effect is related to waves such as sound or light. the effect causes an increase or decrease in the frequency of sound light or other waves when the souces either move towards or away from the observer. For example the siren of the train to a person on the platform, the redshift seen by astronomers.
Therefore, The Doppler shift can be observed when the source of sound moves towards an observer From a place closer to the observer than the last wave's crest, each consecutive wave crest is sent. Each wave therefore, takes a little less time than the preceding wave to reach the observer.
A circuit has a current of 3 amps and is using a 9 volt battery. The circuit has a resistance of ____
ohms.
Answer:
so 9/3=3 current is 3 amperes
Explanation:
The fomula to calculate resistance is:
voltage/cutrent
9 V/3 A= 3 ohms
A student said,Today, giraffes have long necks that allow them to eat leaves high in trees. They got longer necks by stretching up for even higher leaves. After many generations, the giraffe’s neck was really long.Do you think the student’s explanation for how the giraffe’s neck became long is correct? Explain.
Answer:
yes because there is also a theory about this I studied in biology
theory name -Lamarck's theory
what is the square root of 64
Answer:
8
Explanation:
Square root means what two same numbers multiplied together equal the same number,
So:
8 × 8 = 64
----------------------------------------------------------------------------------------------------------------
Have a good day :)
11. (a)What downward force is acting on you when you go down a waterslide? (b)What type of friction is
present? (c)If the waterslide were dry explain what type of friction in would be and (d)how that
changes your speed? (4 points)
Answer:
a) "gravitation" is the force causing you to go down a waterslide
b) It is "fluid friction" as a solid object (our body) moves over a fluid (the water)
c) It would become "sliding friction" since two solid surfaces slide over each other
d) fluid friction being the weakest friction, switching to sliding friction means a higher decrease in speed and therefore removing the water from a slide will decrease our speed
Solve for resistance. I do not get it. Pls help
Answer: I think a
Explanation:
Motion is
displacement
a change of position in relation to another object
an object you look at to determine if something is moving
speed
Explanation:
When something is moving, we call it is in motion. It can be also defined as a change of position in relation to another object.
When an object is not moving at all, we call that it was at rest.
To be in motion, there must be a change in position.
Hence, the correct options are "a change of position in relation to another object" and "something is moving".