Answer:
When the elevator is accelerating downward, the person feels lighter due to the downward normal force being less than the person's weight.
Explanation:
A person riding in an elevator subjected to a series of unbalanced forces depending on the direction the elevator is travelling.
Two forces are acting on the person; the force of gravity and the upward normal force from the elevator.
When the elevator is going upwards with acceleration a, the person feels heavier than his normal weight, due to the upward normal force being greater than the person's weight. N = mg + ma
When the elevator is moving downwards with acceleration a, the person feels lighter due to the downward normal force being less than the person's weight. N = mg - ma
However, when the elevator is moving up or down at constant velocity ie. acceleration a = 0, the person experience a normal force equal to weight. N = mg
When the elevator is moving downwards with acceleration a = g, the person experiences weightlessness. N = (mg - mg) = 0
A submarine is built to dive to a depth of 90 m where the pressure in the water is about 1 MPa. The engineers want to build a window in the submarine, but the window can only take a force of 10 kN safely. What is the largest surface area window that can be used?
Answer:
The largest surface area window that can be used is [tex]A=0.01\ m^2[/tex]
Explanation:
Pressure
The pressure is defined as force per unit area. The SI unit for pressure is the Pascal (Pa), defined as Newton per square meter.
If a force F acts on a surface area A, the pressure is calculated as:
[tex]\displaystyle P=\frac{F}{A}[/tex]
The pressure at a depth of 90 m is P=1 Mpa= 1,000,000 Pa and the submarine's window can only take a force of F=10 kN=10,000 N.
We need to calculate the largest surface area of the window. We can solve the equation for A:
[tex]\displaystyle A=\frac{F}{P}[/tex]
Substituting:
[tex]\displaystyle A=\frac{10,000}{1,000,000}[/tex]
[tex]A=0.01\ m^2[/tex]
The largest surface area window that can be used is [tex]\mathbf{A=0.01\ m^2}[/tex]
A 3kg ball moving at 8 m/s strikes a 2kg ball at rest,if the collision is elastic,what is the speed of the lighter ball if the heavier ball moves at 2m/s in the opposite direction
Answer:
Speed of lighter ball is 4 m/s.
Explanation:
Applying the principle of conservation of linear momentum,
momentum before collision = momentum after collision.
[tex]m_{1}[/tex][tex]u_{1}[/tex] + [tex]m_{2}[/tex] [tex]u_{2}[/tex] = [tex]m_{1}[/tex][tex]v_{1}[/tex] - [tex]m_{2}[/tex][tex]v_{2}[/tex]
[tex]m_{1}[/tex] = 3 kg, [tex]u_{1}[/tex] = 8 m/s, [tex]m_{2}[/tex] = 2 kg, [tex]u_{2}[/tex] = 0 m/s ( since it is at rest), [tex]v_{1}[/tex] = 2 m/s, [tex]v_{2}[/tex] = ?
(3 x 8) + (2 x 0) = (8 x 2) - (2 x [tex]v_{2}[/tex])
24 + 0 = 16 - 2[tex]v_{2}[/tex]
2[tex]v_{2}[/tex] = 16 - 24
2[tex]v_{2}[/tex] = -8
[tex]v_{2}[/tex] = [tex]\frac{-8}{2}[/tex]
= -4 m/s
This implies that the light ball moves at the speed of 4 m/s in the opposite direction of the heavier ball after collision.
A 12 kg object speeds up from an initial velocity of 10 m:s-1
north to a final velocity of 15 m.s-north. Calculate the
change in momentum.
Select one:
a. -60 kg.m/s
b. 60 kg.m/s
C. -80 kg.m/s
d. 300 kg.m/s
Momentum = m • v
Original momentum = m • 10 m/s north
Final momentum = m • 15 m/s north
Change = m • (15 - 10) m/s north
Change = m • +5 m/s north
Change = +60 kg-m/s north
What is an electromagnetic wave?
A. An induced electric current
B. Vibrating electric and magnetic fields
C. Oscillating electric current
D. An electromagnet
Convert 14 minutes to seconds.
(What unit do we want)
1. Seconds
2. Minutes
Answer:
Seconds...
Explanation:
explain what happens when particles collide
Answer
they transfer energy
What allows us to categorize rocks into the three rock types: Igneous, Sedimentary, and Metamorphic?
Whether or not the rock melts
Involvement of sediment
Process of formation
O Magma or weathering.
Answer:process of formation
Explanation:
Opal is making a list of the uses of electromagnetic radiation. Which of the following should Opal NOT include in her list?
A. A man using a microwave to boil water
B. A submarine using sonar to locate a ship
C. A girl using a remote control to change television channels
D. A hospital using an X-ray machine to take a picture of a broken bone
Answer:
A.
Explanation:
A man using a microwave to boil water
Answer:
d
Explanation:
The SI unit of average speed m.s. True or False. But is there difference between m/s and m.s.
Answer:
false
Explanation:
there is difference in m/s and m.s
On Planet X, an astronaut has maximum walking speed of 1.9 m/s. The astronaut's legs are each 1.3 m long. What is the constant of acceleration due to gravity on Planet X?
A. 8.3 m/s2
B. 2.8 m/s2
C. 3.8 m/s2
D. 1.1 m/s2
Answer:
Acceleration due to Gravity:
Explanation:
Here g is acceleration due to gravity. So C. 3.8 m/s2
A water tank is filled with up to 3.5 m height.Calculate the pressure given by the tank at its bottom
Answer:
96.04Pa
Explanation:
height=3.5m
gravity=9.8%
density=9.8/3.5
=2.8
Preassure=h×g×d
=3.5×9.8×2.8
=96.04Pa
The diagram shows the forces acting on an object at an instant of time. Which of
the following statements about the forces is true? Select one answer.
Answer:
The correct option is;
The object is in horizontal equilibrium but NOT in vertical equilibrium
Explanation:
The given given forces in the force diagram are expressed in vector form as follows;
Topmost force = 2·i + 3·j
The horizontal force = 3·i
The force at the lower section = -5·i - 2·j
Adding the forces together to find the resultant force gives;
[tex]F_R[/tex] = 2·i + 3·j + 3·j + (-5·i - 2·j) = 5·i + 3·j - 5·i - 2·j = 0·i + j = j
[tex]F_R[/tex] = j
Therefore, the horizontal component of the forces are balanced as they cancel out and the object is said to be in horizontal equilibrium
However, the object has a net total resultant force component in the positive vertical direction, the object is not in vertical equilibrium.
A diver runs horizontally off the end of a diving board with an initial speed of 1.95 m/s. If the diving board is 2.00 m above the water, what is the diver's speed just before she enters the water
Answer:
V = 6.56 m/s
Explanation:
in order to find the speed of the diver before she enters we need to find the vertical component of its final velocity by using 3rd equation of motion:
2gh = Vy² - V₀y²
where,
g = 9.8 m/s²
h = height = 2 m
Vy = Vertical Component of Final Velocity = ?
V₀y = Vertical Component of Initial Velocity = 0 m/s
Therefore,
2(9.8 m/s²)(2 m) = Vy² - (0 m/s)²
Vy = √39.2 m²/s²
Vy = 6.26 m/s
Assuming negligible air friction, the x-component of the final velocity will be the same as the initial velocity:
Vₓ = V₀ₓ = 1.95 m/s
Hence, the final velocity will be:
V = √(Vₓ² + Vy²)
V = √[(1.95 m/s)² + (6.26 m/s)²]
V = 6.56 m/s
is the force that opposes the motion and therefore, tries to stop
or slow down a moving body.
e fuole
Answer:
Friction is the force between an object in motion and the surface on which it moves. Friction is the external force that acts on objects and causes them to slow down when no other external force acts upon them. Inertia is the tendency of a body in motion to remain in motion.
Answer:
Explanation:
Friction is the drive between an object in motion and the surface on which it moves. Friction is the outside constrain that acts on objects and causes them to moderate down when no other outside drive acts upon them.
The average velocity of an object over 6.0 seconds interval is 2 m/s what is the total distance traveled and M by the object doing this time interval
Answer:
The answer is 12 mExplanation:
The distance covered by an object given it's velocity and time taken can be found by using the formula
distance = velocity × time
From the question we have
distance = 2 × 6
We have the final answer as
12 mHope this helps you
kinetic energetic plus potential energy is called
What is the average acceleration of a tennis ball that has an initial velocity of 6.0 m/s [E] and a final velocity of 7.3 m/s [W], if it is in contact with a tennis racket for 0.094 s?
Given :
The average acceleration of a tennis ball that has an initial velocity of 6.0 m/s.
and a final velocity of 7.3 m/s.
It is in contact with a tennis racket for 0.094 s
To Find :
The average acceleration of the tennis ball.
Solution :
We know, average acceleration is given by :
[tex]a_{avg}=\dfrac{Final \ velocity-Initial\ velocity}{Time\ Taken}\\\\a_{avg}=\dfrac{7.3-6.0}{0.094}\ m/s^2\\\\a_{avg}=13.83\ m/s^2[/tex]
Therefore, average velocity is given by 13.83 m/s².
Hence, this is the required solution.
Does water pressure depend on the total amount of water present?
(Will pick brainliest)
Answer:
No, because pressure is determined by force and the area over which that force acts.
Explanation:
Please identify the type of inference happening at letter A and the type of interference happening at letter B. If this was a sound wave, which (A or B) do you think would be louder and why?
Answer:
B i think
Explanation:
B because it travels in the same wavelentgh.............
[tex]gjkrejktg[/tex]
Type A is constructive interference and Type B wave gives destructive interference. The constructive interference would be louder.
What is interfernece?Interference can be described as a natural phenomenon that occurs at every place and at every moment. Interference can be defined as the phenomenon in which two waves superpose to produce the resultant wave of the lower, higher, or same amplitude. Light waves are produced randomly by most of the sources.
The interference of light from the soap bubble which reflects colors when illuminated by a light source. The starting point of the wave produced may be a maximum or a minimum, and there is no way to predict which phase the wave will start.
Interference can either be constructive interference or destructive interference. Constructive interference occurs when the crest of one wave falls on the crest of another wave and the amplitude is maximum.
In destructive interference, when the crest of one wave falls on the trough of another wave and the amplitude is minimum. The phase and displacement of these waves are not the same.
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Lead-202 has a half-life of 53,000 years. How long will it take for 15/16 of a sample of lead-202 to decay?
106,000 years
159,000 years
212,000 years
265,000 years
(Thank you very much :L)
Answer:
C. 212,000 years
Explanation:
believe me it's correct.....and you're welcome :)
What is the current in the 10.0 resistor?
Answer:
12.0V
12.0V
Explanation:
.
.
.
.
.
.
.
.
.
.
.
Answer:
2.00 A
Explanation:
29. Identify whether each of the following is a form of mechanical energy:
elastic potential energy, chemical potential energy, gravitational potential
energy.
Explanation:
elastic potential energy, chemical potential energy, and gravitational potential energy are all forms of mechanical energy.
Mechanical energy includes elastic potential energy, chemical potential energy, and gravitational potential energy.
What is Mechanical energy?Mechanical energy is the energy that an object has as a result of its motion or position. Because it is stretched out in that position, a pulled bow has mechanical energy (elastic potential energy). Chemical potential energy is the energy that a substance has stored in its chemical bonds. A barbell hoisted high above a weightlifter's head has mechanical energy because of its vertical position above the ground (gravitational potential energy).The sum of kinetic and potential energy in an object used to perform a specific task is known as mechanical energy. In other words, it describes the energy of an object as a result of its motion, position, or both.
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The planet Jupiter is about 300 times as massive as Earth, but an object on its surface would weigh only 2.5 times as much as it would on earth. Can you come up with an explanation?
Answer:
here you go
Explanation:
so it might seem that a body on the surface of Jupiter would weigh 300 times as much as on Earth. ... But the radius of Jupiter is about 10 times that of Earth, weakening gravity by a factor of 100, resulting in 3 times its Earth weight.
A bugatti chiron travels 116 m/s for 10 seconds.how far did it travel
Answer:
V= 1,160 m
Explanation:
formula:
V= V* T
remplazamos:
V= 116m /s * 10s
V= 1,160 m
Answer:
V= 1,160 m
Explanation:
005 (part 1 of 2) 10.0 points
A runner is jogging in a straight line at a
steady vr= 8.5 km/hr. When the runner is
L=6.4 km from the finish line, a bird begins
flying straight from the runner to the finish
line at vý= 17 km/hr (2 times as fast as the
runner). When the bird reaches the finish
line, it turns around and flies directly back to
the runner
What cumulative distance does the bird
travel? Even though the bird is a dodo, as-
sume that it occupies only one point in space
(a "zero" length bird). travels in a straight
line, and that it can turn without loss of
Speed
Answer:
7.53 km
Explanation:
We at given;
Speed of runner; v_r = 8.5 km/hr
Speed of bird; v_y = 17 km/hr
L = 6.4 km
We know that; time = distance/speed.
We are told that the bird starts from 6.4 km from the start and that it flies back to meet the runner after it reaches the finish line. If the total distance back to the runner is x, it means bird distance is 6.4 + (6.4 - x) = 12.8 - x
Thus;
Time of bird(t_y) = (12.8 - x)/17
Thus,
Time of runner(t_r) = x/8.5 hr
To find x, we have to equate the times of the runner and the bird.
Thus;
x/8.5 = (12.8 - x)/17
Multiply both sides by 17 to get;
2x = 12.8 - x
2x + x = 12.8
3x = 12.8
x = 12.8/3
x = 4.27 km
Thus, cumulative distance traveled by bird is; 12.8 - 4.27 = 7.53 km
Which of the following equations is balanced?
a. 2Al2O3 -----> 3Al + 3O2
b. 3Al2O3 -----> 3Al + 2O2
c. 2Al2O3 -----> 4Al + 3O2
d. 2Al2O3 -----> Al + 3O2
Answer: c
Explanation:
The way to check which one is the correct one is to simply multiply and see if there are the same number of atoms in both sides for each element.
a. 2×2 atoms of Al ≠ 3×1 atoms of Al
2×3 atoms of O = 3×2 atoms of O
BOTH MUST BE EQUAL FOR IT TO BE ADJUSTED!!!!!
b. 3×2 atoms of Al ≠ 3×1 atoms of Al
3×3 atoms of O ≠ 2×2 atoms of O
c. 2×2 atoms of Al = 4×1 atoms of Al
2×3 atoms of O = 3×2 atoms of O
BOTH ARE EQUAL, CORRECT ANSWER!!!
d. 2×2 atoms of Al ≠ 1×1 atoms of Al
2×3 atoms of O = 3×2 atoms of O
The south pole of one bar magnet is near the south pole of another bar magnet. What happens between the magnets?
A. They attract each other.
B. They twist toward each other.
C. They neither attract nor repel each other.
D. They repel each other.
PLEASE HELP!!!!!!!!!!
The south pole of one bar magnet brings near the south pole of another bar magnet, they repel each other. Therefore, option (D) is correct.
What are the magnets?A magnet can be defined as an object which is capable of producing a magnetic field and attracting unlike poles and repelling like poles. When a magnet dropped in iron filings, the iron filings cling to the end of the magnet as the attraction is maximum at the ends of the magnet.
Magnetic poles always exist in pairs whenever a magnet is suspended freely in the air, and always points in the north-south direction. The pole pointing towards the geographic north is called the North Pole and the pole pointing towards the geographic south is called the South Pole.
Similar poles of a magnet repel while unlike poles attract each other. The magnetic force between the two magnets is higher when the distance between these magnets is lesser. There are three types of magnets which are Permanent magnets, Temporary magnets, and electromagnets.
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What is the net force on this box?
Answer:
I believe 0
Explanation:
this is due to the fact that the box will not move anywhere the forces are canceling themselves out.
Please help me fast
Answer:
b I think. sorry if it's wrong
Can someone Plzzz help meee.
solid...............