Answer:
The kilogram (kg) is defined by taking the fixed numerical value of the Planck constant h to be 6.62607015 ×10−34 when expressed in the unit J s, which is equal to kg m2 s−1, where the meter and the second are defined in terms of c and ∆νCs.
why watchman does no work but gets tired ?
Answer: the body is trained to wake up when the sun rises and get the energy from the sun and sleep and it is night on when the sun is not there. So when a watchman works at night there is no sun first of all to give him any kind of energy and secondly the body clock resists him waking up thus making him tired.
Explanation:
1. A man is running on the straight road with the uniform velocity
3 m/s. Calculate acceleration produced by him.
(a) As you ride on a Ferris wheel, your apparent weight is different at the top and at the bottom. Explain. (b) Calculate your apparent weight at the top and bottom of a Ferris wheel, given that the radius of the wheel is 7.2 m, it completes one revolution every 28 seconds, and your mass is 55 kg.
Answer:
a. The component of the net force which make up the apparent weight are added to each other at the bottom and subtracted (the centripetal force from the weight) at the top)
b. Apparent weight at the top is approximately 519.06 N
Apparent weight at the bottom is approximately 558.94 N
Explanation:
a. The apparent weight at the top is different from the apparent weight at the bottom of a moving Ferris wheel because of the opposite direction in which the centripetal force acts at the top and the bottom, which are upwards and downwards respectively, while the weight acts downwards constantly
b. The given parameters are
The radius of the Ferris wheel, r = 7.2 m
The period for one complete revolution, t = 28 seconds
The angle covered in one revolution, θ = 2·π radian
The mass of the person riding on the Ferris wheel, the passenger = 55 kg
Therefore, we have;
The angular speed, ω = Δθ/Δt = 2·π/(28)
From which we have;
Centripetal force, [tex]F_c[/tex] = m × ω² × r
Substituting the known values, we have [tex]F_c[/tex] = 55 kg × (2·π/(28 s))² × 7.2 m ≈ 19.94 N
The centripetal force, [tex]F_c[/tex] = 19.94 N always acting outward from the center
Weight = Mass × Acceleration due to gravity
The weight of the passenger = 55 kg × 9.8 m/s² = 539 N
The weight of the passenger = 539 N always acting downwards
At the top of the Ferris wheel the the centripetal force is acting upwards and the weight is acting downwards
Therefore;
The net force, which is the apparent weight of the passenger at the top [tex]F_{NET_{Top}}[/tex] = 539 N - 19.94 N ≈ 519.06 N
Apparent weight at the top ≈ 519.06 N
At the bottom of the Ferris wheel the weight is acting downwards and the centripetal force is also acting downwards
Therefore;
The net force at the bottom, which is the apparent weight of the passenger at the bottom [tex]F_{NET_{bottom}}[/tex] = 539 N + 19.94 N ≈ 558.94 N
Apparent weight at the bottom ≈ 558.94 N.
A sharp knife cut things easily
Answer:
its due to less surface area of action
pressure is high
explain why an inflated balloon is likely to burst if you leave it near a window with the sun streaming it?
Answer:
the sun light will heat up the balloon causing it to burst
Which of the following does not illustrate a complete circuit?
Answer:
I think A
Explanation:
because it dosn't have enough tools
Choose the answer that is most descriptive of the Solar System. Sun, planets, moons, asteroids, comets Nebulas, star clusters, super nova, black holes, binary stars Jupiter, Neptune, Saturn, Uranus, dwarf planets Jupiter, Great Red Spot, 8 regular moons, ±58 irregular moons
Answer:
The correct option is;
Sun, planets, moons, asteroids, comets
Explanation:
The Solar System consists of the system of celestial bodies bound gravitationally to the Sun, which includes the 8 regular planets, 2 dwarf planets, 796, 354 known minor planets, 4,143 comets, moons, which are natural satellites, an asteroid belt, which consists of a belt of rock and metal containing celestial bodies moving in a belt round the Sun
When food is digested, the
smell changes considerably.
What would you call this type
of change?
A. A physical change
B. A chemical change
C. A solution change
Answer:
Chemical change
Explanation:
A chemical change is what happens. The food digested changes smell due to some enzyme the has acted on the food which catalyzes the rate of digestion. The enzymes acts on the food in order to speed up the rate of the reaction (digestion) and in turn causing the smell.
Calculate the kinetic energy of a 50 kg cart moving at a speed of 18.6 m/s.
Answer:
8649 J
Explanation:
KE = 1/2mv^2
1/2(50)(18.6)^2
1/2(50)(345.96) = 8649 J
A washing machine is being dragged with a starting force of 380.8 N to the West, but this is reduced by friction. If the mass of the washing machine is 37 kg
and the coefficient of friction is 0.54, what was the Net acceleration experienced by the washing machine?
A 10.27 m/s^2 South
B 5 m/s^2 South
C 19.01 m/s^2 South
D 7.6 m/s^2 South
Answer:
B. [tex]5\,\frac{m}{s^{2}}[/tex] South
Explanation:
The correct statement is:
A washing machine is being dragged with a starting force of 380.8 N to the South, but this is reduced by friction. If the mass of the washing machine is 37 kg and the coefficient of friction is 0.54, what was the Net acceleration experienced by the washing machine?
The net force of the washing machine moving on the horizontal ground is equal to the external force minus the friction force, where the normal force from the ground on the washing machine is equal to its weight. The free body diagram of the washing machine is presented below. The equation of equilibrium associated with the acceleration of the washing machine is:
[tex]\Sigma F = P -\mu_{k}\cdot m \cdot g = m\cdot a[/tex] (1)
Where:
[tex]P[/tex] - External force exerted on the washing machine, measured in newtons.
[tex]\mu_{k}[/tex] - Kinetic coefficient of friction, dimensionless.
[tex]m[/tex] - Mass, measured in kilograms.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
[tex]a[/tex] - Net acceleration of the washing machine.
If we know that [tex]P = 380.8\,N[/tex], [tex]m = 37\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]\mu_{k} = 0.54[/tex], then the net acceleration experienced by the washing machine is:
[tex]a = \frac{P}{m}-\mu_{k}\cdot g[/tex]
[tex]a = \frac{380.8\,N}{37\,kg}-(0.54)\cdot \left(9.807\,\frac{m}{s^{2}} \right)[/tex]
[tex]a = 4.996\,\frac{m}{s^{2}}[/tex]
The correct answer is B.
Which one of the following is not a member of the solar family: (a) Morning Star (b) Evening Star (c) Pole Star (d) Tailed Star plzzz answer this...
Answer:
Tailed star
Explanation:
Tailed star
4 pleasee i have to submit in 10 minutes
Answer:
True
Explanation:
An object has a force of 29.43 N acting on it. Its acceleration is 3.5 m/s2. What is the mass of this object?
Answer:
The mass of the object is 8.41 Kg.
Explanation:
Mechanical Force
The second Newton's law states that the net force exerted by an external agent on an object of mass m is:
F = m.a
Where a is the acceleration of the object. The SI unit for the force is the Newton: [tex]1\ Nw = 1~Kg.m/s^2[/tex]
We are given the net force of F=29.43 N acting on an object and producing an acceleration of a=3.5~m/s^2.
To calculate the mass of the object, we solve the above equation for m:
[tex]\displaystyle m=\frac{F}{a}[/tex]
[tex]\displaystyle m=\frac{29.43}{3.5}[/tex]
Calculating:
m = 8.41 Kg
The mass of the object is 8.41 Kg.
Which best compares radiation and conduction?
A. Both transfer thermal energy from warm objects to cooler objects.
B. Both can transfer energy through empty space.
C. Both transfer thermal energy by electromagnetic waves.
D. Both involve the transfer of energy through direct contact.
And also who likes Rick and Morty OwO
Answer:
A
Explanation:
g. Write the merits and demerits of ultraviolet rays.
Answer:
UV rays aid in the production of Vitamin D. But it can also give you cancer.
Explanation:
i am a scientist
An alkane has molecular weight 86. Write its molecular formula. What will be its physical state?
C6H14
Gaseous state
it's unsaturated hence gaseous
calculate the kinetic energy of running kitten that has a mass of 4 kg and velocities of 2 m/s
Calculate the mass of a man jogging north along the highway at a rate of 2.65 m/s and a momentum of 225.3 kg*m/s
Answer:
85.02 kgExplanation:
The mass of the man can be found by using the formula
[tex]m = \frac{p}{v} \\ [/tex]
v is the velocity
p is the momentum
From the question we have
[tex]m = \frac{225.3}{2.65} \\ = 85.01886...[/tex]
We have the final answer as
85.02 kgHope this helps you
A pinball bangs against a bumper of a pinball machine with a speed of 0.46 m/s. If the ball has a mass of 0.058 kg, what is the ball's kinetic energy?
This needs to be done in 3 mins
Answer:
Okay I might be wrong and sorry if i am either its 12 or 0.402
Explanation:
* I recommend the second one cause its more logical
Be aware I might be wrong
When the net force on an object is zero, what do we know about the motion of that object
Answer:
The objects speed or motion does not change if the net force is 0.
Explanation: There basically doesn't have anything acting on it so it stays put.
Which are compounds ?
Answer:
water, salt, ammonia, sulfuric acid
Explanation:
I looked it up and decided to be helpful
Answer:
Water, Salt, Ammonia, Sulfuric Acid
Explanation:
If you could change one property of a substance ( solid, liquid, and gas) you have to use in your daily life, what would it be and why?
Please hurry
I will give you BRAINLIEST!!!!!!
And pleaseee write 5 sentences why??
Answer
Soap into a liquid
Explanation:
Which of the following is the most sensible way to conserve natural resources?
O Don't use any products made from trees
O Stop using electricity entirely
Never ride in a car
O Bike or walk to school instead of taking a gasoline-powered car.
Answer:Bike or walk to school instead of taking a gasoline powered car.
Explanation: gasoline is not infinite. trees can be replanted and regrown. electricity can by generated and is not a natural recourse.
An object is falling from a height of d and reaches a final velocity of vf. Calculate velocity when the object has fallen a distance d/2.
Answer:
The final velocity, [tex]v_{f}[/tex], is gd.
Explanation:
The condition here is a free falling object. Thus from the third equation of motion under free fall, we have;
[tex]v_{f}[/tex] = [tex]v_{i}[/tex] + 2gs
where [tex]v_{f}[/tex] is the final velocity of the object, [tex]v_{i}[/tex] is the initial velocity of the object, g is the gravitational force and s is the height.
Since the object falls from a height of d, then [tex]v_{i}[/tex] = 0 m/s, and s = d.
So that;
[tex]v_{f}[/tex] = 0 + 2gd
= 2gd
[tex]v_{f}[/tex] = 2gd
When the distance is [tex]\frac{d}{2}[/tex], [tex]v_{i}[/tex] = 0 m/s.
Then;
[tex]v_{f}[/tex] = 2g[tex]\frac{d}{2}[/tex]
[tex]v_{f}[/tex] = g x d
When the object falls through the height [tex]\frac{d}{2}[/tex], then the final velocity is gd.
HELP ASAP!! WILL TRY TO GIVE BRAINLIEST
Explain how receptor-mediated endocytosis is more specific than pinocytosis or phagocytosis
Answer:
it selects what molecules to engulf, whereas pinocytosis or phagocytosis engulf anything in the vicinity
Trust!
The air is an example of a gas in a gas solution. True or false
How does an executive order differ from a statue?
Answer: Executive Order on Protecting American Monuments, Memorials, and Statues against our country are public monuments, memorials, and statues.
Explanation: learned it last week
A weightlifter takes 0.5s to raise a barbell with 2 free-weights from the ground to a height of 0.9m. If each free-weight has a mass of 30kg and the barbell has a mass of 20kg, calculate how much power the weightlifter produces when lifting the barbell?
Answer:
P = 1412.82 [Watt]
Explanation:
First we must calculate the total mass that makes up the barbell and the two free weights at each end of the barbell.
[tex]m=30+30+20\\m= 80 [kg][/tex]
Weight is now defined as the product of mass by gravitational acceleration.
[tex]w=m*g[/tex]
where:
m = mass = 80 [kg]
g = gravity acceleration = 9.81 [m/s²]
[tex]w=80*9.81\\w=784.8[N][/tex]
Now using the product of the weight by the distance traveled we can calculate the work.
[tex]W=w*d[/tex]
where:
W = work [J]
w = weight = 784.8 [N]
d = distance = 0.9 [m]
[tex]W=784.8*0.9\\W=706.41[J][/tex]
And power is defined as the relationship of work at a certain time. The potency is expressed by means of the following formula.
[tex]P=W/t\\P=706.41/0.5\\P=1412.82[W][/tex]
Which best defines gravity?
A. The tendency of objects to fall from trees
B. An attractive force between two objects due to their mass
C. The amount of matter in an object
D. The rate at which objects fall to earth
Answer:
B. An attractive force between two objects due to their mass
Explanation:
Answer:
B
Explanation:
Gravity is a force that pulls 2 objects towards each other and varies depending on mass. The earth for example is large enough to have a gravitational force that keeps us down. The sun has a gravitational force that keeps the Earth in orbit.
the diagram shows the apparent motion of the sun across the sky?
Answer:
The earth rotates west to east
Explanation:
Considering that the sun doesn't really move and the earth is rotating around the sun, and it is moving from east to west with us (the earth) facing it in which means the earth rotates around the sun west to east!